RE: valves:mechanical vs electronic
UP valves all the way. I have a UP-2 and a UP-4 valve on my Eurosport that's been around for 6 seasons at least. I took it all apart for a repainting and renovation and when I re-plumbed the retracts and tested them, they still worked perfectly! All my jets have UP-6 on brakes - the most reliable, best brake valve on the market.
Bob