I can honestly say I think it belongs in every Wii-owner's collection.
The takeaway: This game is a blast, and you should buy it. BUT, it's not perfect.
First Impressions:
1. The graphics are great; cell-shading rocks on the Wii, so it's nice to see it done so well. I never saw hiccups in the framerate, so I'm happy. The visual style really fits the game, the feeling it's going for, and your sense of immersion as a player.
2. I really like the music. It's a great mix of western and eastern themes, with more of a gritty (versus twangy) feel. Think of the amazing Neil Young music on the Jarmusch "Acid Western", Dead Man.
3. The voice acting is forced and odd, at times. No argument there. I don't care.
4. Controls are good. I never found a "sweet spot" right out of the gate like I have on other FPS-style games, but after 20 minutes I was riding with no training wheels.
5. Gameplay is mixed, with the best parts (combat) getting the most attention, thankfully. Exploration can be "meh" at times, but it normally leads to more combat quickly enough.
6. Combat techniques are good, and you can mix your bag of tricks and still feel like you're playing the game the way it's meant to be played. I never felt like the controls caused me problems, just my memory of the moves.
Conclusion: I think you should just buy this game. It's good, and you deserve to play it.