Is buying dropped High PR Domains for new websites help SEO and drive traffic fast to the website with minimal efforts ?
Buying high pr domains will increase your money site rank. However I would say that it takes more than minimal effort. Unless you pay a higher dollar for backlinking services and it is done pretty much for you.
I've never had any luck with expired domains. When you buy a domain someone else previously owned, you're buying their history and backlinks. You can't get rid of the history either, so it's always a good idea to thoroughly research domains before buying them.
This used to be a really common practice just couple years ago but now with all the mess with domain brokering its significance is declining. It makes sense only if the name contains really good keyword you need and the PR is high. You need to check the domains' backlinks history really thoroughly.
If a domain is PR5 with thousands of backlinks and about 40 gov & edu backlinks.. I think it is worth it ?
For sure such a domain's a cool buy, just check out those thousands -- if you find that half of them are from torrent and adult sites.... You know what to do
Clean links.. I think this domain with some fresh original content will do well. I expect at least 1000 visits per day after 1 month (already having traffic)