The URC unis by Mad4One are the cheaper range by Mad4One. To me, the essential difference really is that its steel, not aluminum so its a bit heavier, and secondly the colour choices are much fewer. You only get an inboard brake mount, not both (but you really don’t need both to be honest). The steel model is a heck of a lot cheaper than the aluminium model though!
In Sydney Australia, loads of people have Mad4Ones. It’s really from word of mouth and people buying them in pretty colours, reasonable prices and the ability to customise that seem to be the reasons why they are popular (just in my opinion). Being sold from Italy doesn’t seem to be so much of a deterrent! There have been shipping delays though, but I think that is largely a Covid issue.
As to being 160cm. Check your inseam, you may have issues riding a 29er and you might need to cut the frame. My inseam is 77cm and I have about 5cm spare on a Nimbus 29er (depends on seat and crank length, I am using 125mm cranks and KH Fusion Freeride saddle), so if your inseam is less than ~72cm, you may want to cut the uni frame down a little at the neck.
As to the best seat, my favourite is the KH Fusion Freeride.