Re: Questions of a Competitive Battling Newbie
I think I can help here.
1. You don't exactly have to hatch a Pokemon from an egg to have it be competitive, but if you start breeding, you can have Pokemon with max IV's, the perfect nature, and some Egg Moves. If you find a Wild Pokemon with the nature you want and good IV's, go ahead and use it if you want.
2. You can use Vitamins whenever, but they don't max out the EV's in a stat. At most, you can get 100 EV's in a stat using vitamins, so you still have to earn another 152 to max out the stat.
3. The Macho Brace doubles the rate of EV gain, so you can get the EV's trained in half the time. Still, if you're willing to challenge the Battle Frontier in D/P/Pt/HG/SS or the Battle Subway in B/W, you can earn Power items, which give you 4 times as many EV's in a stat. So with a Power Weight, I get 4 EV's for every Bidoof I beat instead of 1.
4. Both are okay to use when training, it doesn't matter how fast you level, so long as you get the EV's before you reach Level 100. Keep in mind that if you use the Exp. Share, it also shares the EV's, so you have to make sure you don't KO the wrong Pokemon when level grinding.
VPP: Giratina, Level100 @ 4,554