Hi Vic, it's still underpowered with the AP .15. I'm really disappointed in that engine...However, MikeSell and I are going to order a bunch of nice, light Norvel .25s from the LHS (we get better than catalog pricing and no shipping when we get a few of us together and buy in bulk. We made an order for 10 .074s and got them for 48.00 each.). That ought to perk it right up.