Autoresponders: Local or Server?

I am just gonna throw this question out there, and hope some Internet Marketing guru takes pity on me and sends along a comment or two. Perhaps Perry Marshall will stop by and provide an answer to this long debated question. Maybe Brad or Matt Callen will wander through and offer up pearls of wisdom. I personally don't know. Part of me likes the control offered by "local" options such as Xtreeme MailXpert and then there is the whole "let the experts do what they do best" thingy in using a web-based solution.

I guess both arguments have merit, but seriously, which is the BEST option? They will probably tell me it depends on what you hope to accomplish. So let's see. What DO I want to accomplish. Well, I want a "list" because everyone says I need one, right? Okay, wrong answer. What about this... I want to be able to send out newsletters to a group of people interested in the material I have to offer. And I don't want to have to address each member individually. And I want something that will handle the bothersome issue of the "double-opt-in" requirement that the spammers of the world (lowest form of life on the planet) have made necessary. And from time to time, I might want to send out a special broadcast of new material that can't wait for the regularily scheduled weekly/monthly/daily newsletter. What else? Oh yeah. I want the emails I send to get through! Past all the spam blocking technology that every ISP and their dog has had to implement because these direct marketers have taken the "junk mail" concept to a whole new level. (Did I mention that spammers are the lowest form of life on the planet?) I think that about covers it. So, guru passing through... based on what I want, which is best? Local or Server based autoresponders?

Your input is GREATLY appreciated!