I dont have experience with what you mentioned aside for the U4T switches, FWIW the switch itself is fantastic, the quality is felt with this one, the housing is tight even after opening the switch, no leaf/spring noise and the tactility is pleasing, with it's releativly low price it really puts to shame other brands.
Though it's a "Holy Panda type" switch, short travel with less linear travel after the bump and loud bang on the housing, AFAIK it's very different from Topre.
People love Topre and from the looks of it and the force curves I've seen it seems like interesting stuff, though I havn't had the chance to try it (maybe one day..).
The biggest pro of the DZ60 build is that you could always change the parts mainly the switches.