Hi mate,
Great thread! I've been wanting to convert my 5B for ages, but the motor mount is the biggest issue for me :(.
Anyway, with regard to looking for a digital servo, is it for steering or brakes or both? I run one of these for my steering and it's been bulletproof.
Multiplex Rhino Digi 4
Even when the steering linkage or servo saver gets jammed up with mud and stuff, servo keeps going.