You either love it, or you hate it. And if you hate it; it's because you don't understand it or you just suck at it.
Graphics and Visuals:
Being a game made for the PSP obviously you cannot expect top-of-the-line graphics in every aspect. However, the cinematics are pretty impressive considering the medium. As for in-game; they are definitely not the best out there but the depth of detail in each weapon, piece of armor, and Wyvern is absolutely stunning. Everything is absolutely unique and interesting in it's own way. About the only thing that they recycle is the re-coloring of some of the Wyverns. Although I believe they make up for this by having different drops/armor sets for the different colors. And not just a different color of the same armor; a completely different looking set with different skills and the "works".
Now while there is no "magic" in the game they do a pretty impressive job fleshing out the different weapon types. Along with this there are hundreds of items; many with their own unique animations and effects. I'll cover the items more fully later on.
Soundtrack and Effects:
Now I'm no expert on sound so this is going to be very brief. The soundtrack is incredible. It really adds a whole extra level of "epic" to the game. Imagine fighting an immense dragon (you don't even reach the knees of some of the larger ones) to a LotR style soundtrack.
As for the sound effects most of the Wyverns have their own individual set of sounds, and most of the items do as well. Good or bad, the shear number of sound effects accounts for something.
The one drawback to the game. There really is no storyline. At least not one that is thrown in your face. There is some plot-line in the form of dialogue between you and the characters in the game, as well as quest descriptions, and some cutscenes. That being said; putting in a storyline that centers around your character would definitely detract from the game. Part of the appeal is that this is YOUR story. You create the plot through your actions in the game. The reason there is no story being thrown in your face is that each players experience is meant to be unique. You are the hunter. It's not their job to tell you your background, who your rivals are, and where you're headed. How you got there is something for you to create. Have a Wyvern that you really just hate? There's your rival. You pick your own outcome. However, they do give you some background on some of the different factions, and characters in the game. And there is a slight rivalry scenario between you and this guy named "Tigrex".
Monster Hunter is unlike any other game out there. As such, comparing it to anything doesn't do it justice, and expecting anything is pointless. It is not a hack and slash. It is not and rpg. It is Monster Hunter. As the name suggests you hunt monsters called "Wyverns". There are many different classifications such as "Bird-Wyverns" that are pretty much what they sound like; bird-like, dragon creatures. "Carapaceons", which are more crab-like than anything. "Pelagus", that are mammalian monsters, generally resembling some type of monkey or ape. "Piscine Wyverns", which are water dwelling. And "Elder Dragons" (self-explanatory), just to name a few.
The main thing I feel I need to warn you about is the difficulty level of this game. The learning curve is VERY steep. Just because you are a good gamer does not mean you will be good, or even kind of alright, at this game. As stated it is unlike anything else out there. The biggest thing that people notice upon picking it up is the lack of a "lock-on" system. However, there is a reason for this; almost every single piece of a monster can be destroyed or cut off and implementing a locking feature would actually hurt you more than it would help. You need a tail or a fang from a particular Wyvern to make that awesome new piece of armor? You have to actually cut off it's tail or break it's teeth to get the part you need. Using your camera properly and attacking at the correct angle IS your "lock-on".
Having covered that section I move on to my next point: character progression. In Monster Hunter there are no levels. There is no skill tree that you advance. As stated, you ARE your character. Your character does not get stronger; you do. Your character does not gain experience points for killing monsters; you do. This game is about skill not "levels". If you suck at it, you will always suck at it until you buckle down and improve your own gaming abilities. Monster Hunter cannot, and never will be, beaten in a day. If you are impatient, or are looking to be "uber" right out of the gate, this game is not for you. However, if you are willing to put in the time required to master this game the sense of accomplishment is never-ending. There is an infinite amount of things to do, Wyverns to kill, armor and weapons to collect and fun to be had. Once you conquer each monster solo you can take the fight online and hunt with your friends. Group play is a completely different animal with different tactics and styles, and harder monsters. Just because you are great by yourself, once again, does not mean you will be good with other players. You must be careful not to hit your teammates or get in their way or you'll get them killed.
To sum it all up, Monster Hunter is a hobby, not a game. If you are willing to invest the thousands of hours to master it you will never regret your decision. This game is not for the weak, or the impatient. It is a real game, for real gamers. If you get frustrated playing it, put it down for awhile, come back later and try again. Keep at it. It's worth every penny and more.