Conrad Johnson PV10A Mods/upgrades

Hey everyone..

I'm looking to get both my CJ PV10a preamp and MF200 solid state amp refurbished and upgraded. I've read several recommendations for Bill Thalmann and Bob Backert... who both seem to do excellent work! I was hoping to reach out to you all and see if anyone could chime in and help me decide who to go with? I'm leaning towards Bill Thalmann as he was technical director for 25 years at Conrad Johnson.. Any advice would be greatly appreciated! Thanks!