I say fuck a trial membership. If you have something that someone wants to buy and give them a choice of paying a few dollars or paying 20 - 30 dollars, what do you think most will choose? Once the surfer joins your site his "retention" will basically be the same. If a surfer doesn't join your site because you don't have a trial, chances are he's not going to recur anyways, so you might as well get the full price up front. I think it's fair to say that over half of your new signups will not recur. (50% is good imo) So say you get 100 signups a day. Would you rather have 400 dollars (4.00 trial) or 2400 dollars??? (24.00 membership).
IMO trial memberships are more for the SUPER BIG SITES that know that they can retain a customer a long time as well as a marketing strategy to get webmasters pushing their programs. (i.e.: big$ per signup programs)
But hey whatever works go for it! I did and am very happy with the amount of extra money it generated for me as well as for my partners pushing my program.
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