Gemini said:
Geld

Stormsong Manor said:
Geld. If you have to ask yourself whether you should geld or not, the answer is always geld :P

And stallions really need no testing after their freshman year. They really won't produce any better unless they've been tested on reeeeeally crappy mares the first time around. Otherwise, you can pretty much assume their breeding performance will stay about the same. Due to new/stronger studs being born, 95% of the time, stallions fall down their LBs year by year instead of bumping up.