NL25 - SPR in action?

[DonkeyChip]

I just finished reading Professional No-Limit Hold Em and I'm trying to slowly work it into my game. I thought this hand was borderline...whaddya think?

NL25 on FT. The player to my left (villain) has been extremely laggy and recently got all-in vs. a smaller stack with 32o on a Q64r flop...he of course caught runner-runner 3s to win it. He has bet every flop when checked to him. The rest of the table has been somewhat aggressive.

I have $14.75 (villain covers) in MP3 and open-raise to .75 with ATs, villain calls, SB calls, BB calls. Pot ~$3.
FLOP: A-8-4 rainbow
SB checks, BB checks, Hero ???

I checked, villain bets $1.50, SB and BB fold, Hero ???

I raised to $4.25, villain calls.

TURN: 2
Hero ??? Pot is ~$11 and I have $9.75 left.

At this point I'm committed (I had decided to go all the way with it once villain bet and the blinds folded)...does it really matter how the rest goes in? Anybody lead the turn for anything less than all-in? FWIW, we did get it all-in on the turn and the river was a Q. Results later.