I would always suggest someone local or known to you so that you can keep tabs on progress and not have to worry about post so much.
The only one I have ever used is a chap at our club.
Decent skills, quick will do armies (assuming no pre-esxisting back log - his work is popular) and has decent prices. He is also well into
AoS which I think might be a bonus for you..
http://fanplasticlittlemen.blogspot.co.uk/