I am resurrecting a early 80's turnaround bird I can occasionally fly in some local meets. It has a 65" inch wing and was setup for a ys 61. I am putting a 91 FS in it and was wondering if anyone had a reasonable objection to using 3151's on a bird like this. I have 0 experiance with the newer futaba servos. I fly mostly IMAC so my servo selecting knowledge is all out of whack.

I used a batch of them on my Ultra Sport. They center better than the non-digital servos, but the bearing is sub standard and moves a lot with pressure on it. Certainly they will work, but I will be using S9153's in the future.

What size was your ultrasport?

Ultra Sport 1000 (80" wingspan, 13lbs 2oz)

I'm finishing up a UFO for which I bought two 3151s and two 3152s. I will use the 3151s for the ailerons and the 3152s for rudder and elevator. I'll be using a 5-cell 6v rx pack and I'm certain these servos will be adequate for a 7 1/4lb plane (54 oz-in and 87 oz-in respectively). Your plane sounds like it's around the 8lb or less range, so I think these are fine. It really just comes down to how much you are willing to invest in an r/c model.