Are all 3 serviceable? Nice display too - when they're working well.
I also have a Quicksilver with maxed-out RAM, which still performs well with OS X Tiger and all the great performance enhanced TFF and other tweaks discussed frequently over in the PPC forum. Suggest you take a look over there, a very friendly crowd - as indeed they are here too.
Unless I'm mistaken, on the far left that's a Power Mac G4 (3.1/3.3) rather than a B&W (G3).
I'm glad to see that you took the initiative to repair that board. I have to admit that I'd have been tempted to just stick a replacement in there.My 733Mhz Digital Audio G4 Tower was a labour of love - acquired for free sans CPU, CPU heatsink, CPU heatsink fan & shroud and had scratched/broken traces near the CPU (directly below the heatsink clips) which I had to trace and bridge with prototyping wire. Somebody had even removed the airport cable from the side panel. Rebuilt over time, and spent probably it's market value in parts, it became a stupid project to prove it could be resurrected. Ran 24x7 as a server for several years but has recently suffered a failed PSU which is under repair status for the time being.
I toyed with getting a QuickSilver 733Mhz at the time, but the QuickSilver CPU at 733Mhz has no level 3 cache.