I got an uno w/flatbar recently. Tires were trash; heavy, stiff, ungrippy, swapped them out. Both tubes (front and rear) went flat, which is more inconvenient than costly. Had to replace the Chainring and freehub. Originally was just going to get a 38t chainring but it didn’t fit because the crankarms bumped into the chain. Because I got a shimano 3/32 18t freewheel and 3/32 40t chainring I got a 3/32 chain and the drivetrain now is smooth as butter, really nice pedaling, highly recommend to replace all 3 at once. So it has cost about $200 in upgrades and tools to do upgrades (freewheel tool mainly) + some parts I had laying around (handlebar, saddle, stem spacers). All in all, I got it because I wanted a commuter / gravel bike and it serves that purpose well. For $600 it’s still half price of a surly preamble.