I agree that the multiple entry system can be tough on the wallet, and can be quite frustrating if you do not play consistently well. If anyone is considering going for it, but hesitant due to this system, I strongly recommend coming out to the Pinburgh tourney in April.
The format is a flat rate fee ($100 I believe), and guarantees 2 FULL days of tournament play (a third if you qualify in one of the groups). The format is just plain fun, and you play with new groups of 3 players after every break. I had a blast, and plan on making every one that I can in the future.
Maybe I will get to the championships one of these years, but I am positive Pinburgh is definitely for me. It is like playing a whole season of pinball league in 2 days!!!!