I think Monster Hunter Tri is great but I wouldn't recommend if you are only going to rent it for about 3 days or less if you are a beginner gamer. However I gotta give this game as many thumbs up as I can but stop at 50. This game is tuff at some parts but throughout you'll get the hang of it. Also if you just started don't go into the Battle Arena.
Okay, first of all, let me get to the good stuff before I get on to my critique. My first word about this game...awesome. Yeah, I admit that despite the flaws I'm about to report, this is a really good game. The creatures look real, they act real, behave according to the descriptions given, seem realistic for the most part, really good characterization customization, and good gameplay all-in-all.
Now on to the critique, let me point out that I spent the first day figuring out how to convert kills into resource points. I'll blame it on the game for not giving me instructions on how to do that, I just messed around with the controls until it did something. I guess they couldn't be bothered to say 'Press the Z button and the A button alternately' that infuriated me.
I also noted some of the most insane poses in this game, like immediately after you heal yourself with a potion or an herb. Your character strikes a position that immediately makes me think 'Bowflex finance this game perhaps?'. Another problem I spotted was when you're 'stunned' and you're in a position where you can't move until something hits you, and that 'thing' is most often a wyvern and will kill you with one more strike. At least give a set amount of time before you snap out of it.
Also, let's get to talking the monster's armor. Apparently, the game seems to believe that wings are armored, and that the creature can fly with armored wings. Despite the fact that there is a weight-to-wingspan ratio that permits the creature to fly, having such dense armor would prevent the creature from jumping let alone flying. How dense is this armor? Apparently, it can block a giant axe coming down in an over-hand swing.
I'm going to say that one of the most difficult creatures I came across is the Barroth. Everything else, even the Lagiacrus, I could put up a decent fight against. For some reason, the game thinks that mud can harden and become stone-like in seconds.