I went through the exact same thing with Constant. Luckily my list at the time was only 30 people LOL. I ended up at Intellicontact (aff link included FYI 
) and have been very happy with them so far. I have averaged about 3 mailings a month or so, but I can do as many as I like. They also have a 15 day free trial. The most important thing is they are gambling friendly. When their acct rep called me, we chatted about it and he was happy to have my business. They are also proactively working on making their services better all the time from what I can tell.
CBW