Hyd. is definately the way to go, if you can afford it. Obviously more expensive than a mech. We bought a 8' 75 ton new from betenbender about 7 years ago. Great machine, it definately takes alot of punishment. Not my favorite brand, but we can't afford Cincinatti. Accurpress also has some nice stuff.
If you've got the time, I'd hit a few auctions. Or do a search on ebay for used brakes.
Hope that helps ya,