This is just my opinion based on what I have seen and heard since I have not assembled and flown mine yet. I think a 125 might be too much for this ARF. I believe the kit version came out a bit heavier - depending on building/finishing techniques. I plan on using a 91 four stroke and the reviews I've read seem to indicate this is a good match. If you really want more, maybe a 110 would be the ticket.

Steve