I was very happy for years with a full-size IBM Model M. At some point, I decided I wanted a TKL form factor, and I was lucky to find an SSK in great condition. Then I rediscovered the Model F. I found an XT for $51 on eBay. It worked with Hagstrom's converter out of the box, but I decided to refurbish it anyway. So, I sanded and repainted the barrel plate, replaced the foam layer, installed a Teensy and Soarer's converter, installed a case-mounted USB connector, cleaned the case and keycaps, and remapped the board to a hybrid ANSI/Mac/HHKB layout. To reflect the remapping, I replaced some caps with ones I had harvested from M122 boards or purchased from Unicomp. The layout still has something to be desired, but it works for me, and I much prefer typing on the XT over typing on my Model M boards.
Having said all this, I also discovered Topre switches along the way, and I have to admit that now I spend more time on my RF 87ub 55g than on any of my buckling spring keyboards.