Putting cost aside (because all the services in this space are relatively the same price), I would look at your primary needs first, that will help you decide which service is best. I use both Aweber and GetResponse, and also iContact. None of them "suck" they just each have a different set of features and offerings. Aweber has some cool features that the others do not, like Blog Broadcasts and Automation Rules, which allow you to automatically unsubscribe a person from when list when they join another. Whereas iContact has an API you can customize to do just about anything, but you'd need experience in that area or someone to do it for you. Right now, I'd say iContact has the most solid reputation and you can feel secure with keeping your list there. Lots of horror stories from my friends and colleagues about losing their lists to Aweber randomly with no warning because of spam complaints. If you need those features go Aweber. If you want peace of mind go with iContact. Hope this helps, cheers!