Hey Larry, which of the two motors you felt was the best combo in the Imitation ?
Neither of those would be my first choice, this airplane could have been designed around the 40VF, and the first piped flights I ever did were with a 40VF in a full-fuse Imitation derivative. It's much steadier-running with much less power burst than a PA40 (UL or regular). A 61 will be OK (my first PA61 flights were ALSO with a further deviation but still an Imitation wing) but you would probably want to use less-than-standard-diameter props, and if so, you don't get the full effect of the 61. That airplane currently hangs on my wall with a 40VF in it, worked perfect the last time I flew it. I flew the same airplane with a PA40 at the 95 NATs and to start with at the 96 NATs, but I switched back to the VF the night before qualifying started.
This is a pretty small airplane by national standards so if you are going to run a 61-88 in it, you had better know how to take breaks and power boosts and be willing to go WAY off the reservation from the standard system setups.
I also ran the 46VF, maybe the first time anyone ever ran a 46VF in a stunt plane, in the same airplane I first ran the 40VF, but at the time, I couldn't see what I would do with the extra power. I could probably figure it out now, however.
BTW, on the other topic, the Stalker 51 set up the way Gordan Delany had his would also be excellent.
Brett