Is it actually that good or are you some sort of Gundam Fanboy?
If you never cared for these types of games before, you won't care for Gundam Musou either. It's more of the same, just prettier/smoother. I haven't played much of it because frankly something feels "off" about the game compared to other Musou titles; it's just not clicking with me, but I will be putting more time into it. One thing I really didn't like is that the 2P co-op play is somewhat botched due to the screen being split vertically instead of horizontally. That sucks.
I never got the appeal of those games. Braindead AI waiting for you to kill them, repeat 1500 times per battle. I just dont get it
Have you actually played one of these games past the first level and on a higher difficulty setting?

Orochi Musou especially will KICK YOUR ASS.
I'm ghey for dynasty warriors but sadly I lack a modern system.
Don't worry about it...you have the English version of the superior Orochi Musou to look forward to playing on PS2 anyway.

What REALLY needs an English release is Sengoku Basara 2. It's the BEST "musou" game of them all, IMO; more beat-em-style level design and more interesting, flashier characters with PERSONALITY. Fun stuff.