Well...
In NL i Like to raise at least 4 BB if nobody limped, and even more on limpers when I have position on them.... well... you always have position on limpers...
1st it builds pots
2nd it gives you a chances at the pot pre flop
3rd it give you a shot at the pot on every flop, even if you dont hit
And belive me if you always raise 4 to 8 BB, you will always have callers and even reraisers on you monster hands... (its kind of my problem right now)
PS.: dont listen a word of what i've just said cause I'm down 1250 BB in my last 4500 hands...
KJ