Agreed. SMF is so much better than phpBB in my opinion. There's so many people out there that use phpBB and say "oh SMF sucks" but the thing is, they've never even tried SMF before. And don't call me one of those people, because I've tried both softwares and can clearly see the contrast.
I run two major (~4k posts a day between them) forums. One is SMF 2, the other is phpBB 3. SMF wins hands down. 1) Superior mod handling. Like phpBB, SMF uses a patch system. However, SMF's is integrated into the software completely, making it far more maintainable and much easier to use for non-programmers. 2) Superior moderation tools. phpBB tracks IP information, but the developers are actively hostile to the idea of crossreferencing it for the purpose of catching spammers, ban evasions, and so on, just as one example. 3) Superior scaling. phpBB offers no direct download for avatars, for example, and it's the only forum software so far to actually deadlock on me due to high activity (Wtf). 4) Superior support. phpBB's team is often derogatory in comparison to SMF's. In addition though, there is extensive documentation and assistance available for optimizing your form. 5) Superior security. How phpBB passed a security audit evaluating user input as executable code, I have no clue. Seriously, if you intend to run a forum of any significant size, feature set and activity, SMF beats the rest of the free competition (save for Drupal) into the ground. Other free options are Vanilla (unique, and fast, but like it sounds, very lightweight), PunBB (its speed edge dies as you add features), BBPress (quick like molasses, its only feature is WordPress integration), MyBB (faster than SMF and phpBB, but lacks polish - certainly a step up from phpBB though), and Drupal (more of a full-fledged CMS, with all the complexity that entails, powerful, fast, not very user friendly, and access control is rather hairy).
Besides what has already been mentioned, the only other real consideration should be security. When your forum is hacked and defaced, all of the other little details are no longer important. phpbb used to be one of the best free forum solutions on the market. Starting several years (3, 4 or even 5 years) ago the phpbb developers dropped the ball in a big way. phpbb forum after forum was hacked, defaced and some never recovered. A lot of forum owners (like a good friend of mine) simply closed their sites instead of having to deal with the weekly or daily hacks. Even though smf is not perfect when it comes to notifying the community when a new security has been released, at least they fix the problems. The last SMF security flaw I heard about was fixed in a matter of days. And until a fix was released, the developers posted a work around to stop the flaw from being exploited. When your dealing with a community of volunteers, there are certain issues that come up. Such as slow responses to support questions, updates in a timely manner,,,,,,. That is just the way it is, and I expect that from people that support a product in their free time. Sometimes free time is very limited or none at all. Its not like they are paid to sit there and reply to your questions. But all things aside, SMF stands above all of the other free forum solutions. MYBB is the new kid on the block. But its got a long way to go. One of the things that turned me off to mybb, one of the developers is opposed to adding a paid membership feature. The topic came up in the mybb forums about a payment processing feature and integrating that with the usergroups. One of the developers stood out because he seemed very hostile to the idea. The plugins for mybb are very limited when compared to smf.
The developers may be opposed to adding that as a default feature, but I believe a rather good plugin is already available at mybbcentral.com for integrating payment with membership. It will cost you 4.99 a year though for access to it and their other plugins. I personally like mybb more than the other free forum scripts, but maybe that is just me.
I installed SMF 1.1.8 and phpBB 3.0.4 on an idle server in an enviroment with no network congestion or other distractions and ran AB on the default welcome post that both forums make when you install the software. I attached the results for tests of both at one and ten concurrent connections. In short, SMF has a 60% higher transfer rate than phpBB with one concurrent connection, and SMF is twice as fast as phpBB at 10 concurrent connections. phpBB seems to maintain the same transfer rate with different numbers of concurrent connections, whereas SMF appears to perform better when there's more concurrent connections.
Do yourself a favor and chose SMF. In phpbb, installing modifications take 20mins. On SMF all you do is click install and the modification is installed for you. So theres no need to spend 20mins- 1 hour, editing your files. SMF is more stable. Modifications are great and basically its really easy to use. So you wont have any difficulties.
I second that request. It would be really interesting to see the results of a side by side test of phpbb, smf and mybb. Personally, I think mybb has some really good potential. It needs some comparison test to show how well it can compete with some of the well established forums. To be perfectly honest, the ONLY reason why phpbb is popular, is because it has been on the market for so long. If phpbb was released last month, instead of years ago - it would be mostly ignored.
SMF kills phpbb. SMF is super quick, simple and more secure, tons of addons and some of the best support forums I've seen. Very easy to customize. Go with SMF.
My own benchmark results differ from joebert's. phpBB is faster than SMF when using an opcode cache, in part because SMF eval()'s its template code. Raw siege results under Apache, higher is better. Caching is enabled on all platforms where the option was available: Apache: raw - BBPress: 46.02 Apache: raw - Drupal: 177.20 Apache: raw - Joomla!: 20.06 Apache: raw - MediaWiki: 25.53 Apache: raw - MyBB: 57.33 Apache: raw - phpBB: 45.21 Apache: raw - PunBB: 107.59 Apache: raw - SMF: 51.69 Apache: raw - Vanilla: 64.26 Apache: raw - WordPress: 18.45 With Opcode cache: Apache: -X- - BBPress: 180.26 Apache: -X- - Drupal: 278.54 Apache: -X- - Joomla!: 34.15 Apache: -X- - MediaWiki: 136.60 Apache: -X- - MyBB: 167.50 Apache: -X- - phpBB: 192.15 Apache: -X- - PunBB: 336.33 Apache: -X- - SMF: 142.97 Apache: -X- - Vanilla: 221.16 Apache: -X- - WordPress: 73.25 SMF is not making use of the user cache in this test. User cache tends to improve performance by ~50%. PunBB drops in speed quickly as you add features, so its speed is rather fleeting. These tests are all on clean installs, so they don't reflect real-world usage very well. Right now: My SMF forum has: 1,879,377 Posts in 28,434 Topics by 3,438 Members. My phpBB forum has: Total posts 166873 | Total topics 4954 | Total members 1227 My MyBB forum has: 7,680 posts in 316 threads by 190 members registered That's a rather huge disparity for me to honestly check raw loads for a developed site. I do have an old backup of Elliquiy (the SMF forum) with a database size roughly mirroring Blue Moon Roleplaying's current one (phpBB), at around ~250 megabytes. If Personal Roleplaying gets to a similar size or if a trusting soul is willing to provide me with a database of such size (sans search index) I would be happy to do a much more realistic 'real world' benchmark between the three.