What are the best Futaba or compatible servos to use for a Morris TopCap? Will the extra speed and/or holding power of digitals be noticeable? Do I need a larger capacity battery if using digitals? Thanks much!

Instead of using some digitals, get some Hitec 605 BB ones. They are high tourque and high speed, plus they wont make a hole in your wallet around 30 bucks each.

I don't know much about futabas. But I have a Standard BB JR 517's all around on mine. I tried hitech 225 plastic geared mini on the rudder I stripped the rudder servo in less than 10flights.

I have a YS 63 w/ 14x4 prop swinging 10k rpm. so I am getting some massive airflow over the hitec 225 plastic geared mini could hold up.

but I have approx 60 flights on plane so far w/ stand JR BB's. and I haven't had a problem yet.

I'm running HS425's and HS225MG (the metal gear ones) on the control surfaces of my Knife. I am also using a HS225BB for the throttle.

I'm pleased with this combination so far.

I agree that you need to look at the Hitec line of servos. They are going to be cheaper than a comperable Futaba and will work just as well.

I have been using JR Standard BB 517's for years with no trouble.

Using Hitec 225MG's on my TopCap without any trouble !

Using std. 425's on mine. 2 seasons of abuse and they seem to be working fine.

i havent flown my topcap yet but i have hitec 425's for all surfaces including throttle