I got minus .9 percent using this optimal calculator thingy. I think it calculates that assuming optimal play based on the exact cards left though, so probably just a tiny bit worse than that.
Correction to JB above:
1. The EOR for 1 ace per deck is -0.005816, so that times 4/6 = -0.0038773
2. Assumed HE 0.5% = -.005
3. Add the two together = -0.0088783 => 0.89% house edge.
The Wizard's table states the EV correction for a removed card is per deck. Hence with 4 aces are removed from six decks, that means 2/3 aces removed per deck.
EV correction would be 2/3*-0.005816 = -0.388%.
Total EV on top is then estimated to -0.888% = ~-0.9%.