I personally don't think you need upgraded mounts. I've done both and the stock ones seem perfectly fine. Obviously if you're going to be down there and do want to change them now, it's better to do it all at once. As for a FSB, I prefer more of a neutral handling car which is why I have matching front and rear bars. But again, it's all about preference. Like Paul said, try it out and see how you like it. A lot of people like a little bit of oversteer.
Just curious, how on earth does your rear endlinks wear out? It's defiantly something I'd change regardless of wear, but this is the first time I've heard of this happening.
"We live for a good time, not a long time."
RIP Colin McRae