Tri is the only MH i played so far, really liked it. Overall the series feels poorly handled though; albeit it's huge success in Japan, every game they've released in the last years comes off as a re-re-re-relelease of a previous game, with one new monster added and graphics from 10 years ago.
I'd like to see a new MH game, done on atleast a current gen console, or better yet pc. The later won't ever happen though, which is a shame. Tri felt so much better if you emulated it on the Dolphin; the Wii version had me rubbing my eyes constantly because i thought my vision was blurred.