My thoughts on the seat on
My thoughts on the seat on my Silvio 2.0:
Others have written about this, but one disappointing aspect of the assembled bike is the fit of the fiberglass seat (which, incidentally, was advertised as carbon fiber when I ordered). The two parts of the seat (pan and back) don't fit together well. After sanding off some protruding corners (wearing a mask, in a ventilated area) there are still irregular gaps on either side of the seat where the fiberglass shows. I would rather have a one piece seat, which would avoid this issue. The front edge of the seat pan rubs paint off of the frame. The seat cushions also don't seem to quite fit the seat. The seat bottom cushion is a different shape from the seat pan, and leaves some uncovered area on the sides, including a couple of bolt heads. The seat back cushion seems too long and butts into the headrest cushion.
I believe these issues with the seat are ultimately cosmetic, and when I'm actually sitting in the seat become non-issues.
As for the issue of fiberglass with a carbon top coat versus full carbon , I'm not sure if I care. The underside of the seat is hard to see once installed. Of course a lighter, stiffer seat would have benefits. If Cruzbike offered this as an upgrade later on, and the price weren't outrageous, I'd probably bite (although part of me says I shouldn't have to pay for an upgrade, having ordered when the seat was advertised as carbon fiber...)