Most of the voice samples aren't even words. They're just grunts and yells. People who were actually well-versed enough in Japanese to form an educated opinion on the performances said the English and the Japanese voices are about equal in quality of delivery.
That said, the battle voices can be turned off if they bother you.
Also, it wasn't a case of lack of money. The Japanese voice actors were simply under contracts that disallowed them from having their contributions used outside of Japan.
For the most part they are grunts and yells till you finish the battle then theres the standard phrase that each character will say etc and I'm a stickler for that kind of stuff.
And about the contracts, that's somewhat true. Due to laws and regulations and rules in Japan, if you want to use the Japanese VA, you will need to form new contracts for all of them and give them the same amount that they originally received. If you noticed, none of xseed games have ever had Japanese voice acting, including The Last Story, which is a Shame. I had to use the undub patch and play it VIA emulator, which I still haven't done yet due to the performance I get with Dolphin with that game.
This is why I really respect nintendo, when they published Xenoblade in EU/NA they forked over the cash for us weaboos, and I gladly purchased it.