I thought I remembered seeing this posted somewhere here, but I couldn't find it, so:
EVs are different for level 5ers. I recommend unchecking Snap when doing EVs, and make sure not to waste EVs.
For example, on Abra:
Abra (both Timid and Modest) only needs 197 speed and 236 special attack. Putting any more evs will be a waste. The rest of the EVs are exactly enough to bring Abra's attack stat by 1.
Oh, also, I'm curious... do Silk Scarf and those things gain any usefulness?
edit: I'm finding that with a +nature, 236 EVs is the maximum EVs to put in a stat. Without a +nature, 196 is the max EVs. I think this applies to HP, too. Apparently it takes about 77-78 EVs to increase a stat by one. I feel this is strangely familiar - I think someone already found the exact number but I don't know who. :\
edit2: I think DVs are significantly more important than normal because of the value of 1 stat point. I've found myself avoiding certain Hidden Powers because of this, but I haven't really tested how significant that 1 stat point is.
both edit2+edit1 are incorrect,stat formula is
Stat = Floor((Level(IV + 2BaseStat + Floor(EVs/4))/100 + 5)Personality)
or Stat = 10 + Level(IV + 2BaseStat + Floor(EVs / 4) + 100)/100
so in Lv 5 them are:
Floor((IV + 2BaseStat + Floor(Evs/4))/20 + 5)Personality) or
15 + Floor(IV + 2BaseStat + Floor(EVs / 4))/20
so 1 IV don't always reduce stat by 1 point,but is equal to 4 Evs
and max Evs is 252 - (2Basestat + IV + 12 mod 20)
edit3: I just realized how easy it would be to get a Belly Drum in with a Sitrus Berry... all it takes is a Belly Drum on a switch, Sitrus Berry fully heals, and you sweep. almost forgot that Cubone can't have Sitrus Berry AND Thick Club because that would be broken. :|