Pee Wee Backplate Conversions - Anyone Experimenting Yet?

I jumped onboard and purchased some of the backplates for the Pee Wees a while back. I remember 1/2A Nut doing some testing at the time. Has anyone else done some real world testing of the setup yet, static runs or flying? Since Cox Int is selling them, surely there have been some tinkerers out there. I've been off building some electric planes and a handful of model rockets lately but am returning to the dark side of Cox-powered model construction now. I'm curious to see how they are working out in the field. My latest project is a Willy Nillies Cub 250 and will have an .020 for power. Trying to decide whether I will use a TD with the large alum tank that Cox Int sells or a backplated Pee Wee with external tank. The plane is small and light enough that a Pee Wee should have plenty of oomph for it. I have a handful of unused Pee Wees lying around and most of my TD .020s are committed to other firewalls. The choice of engine setup will determine where I place the firewall during construction. Thanks.