I just bought a brand new Time RXR Ulteam red 2010 (I must be at 27 the youngest non-pro human being who can say that

The 2010 model, at least very few of them to my understanding, came with no seatclamp but only a wedge bolt that you need to drill the front of the seat tube to install.
My question is the following:
Is that bolt is safe to use alone or I'd be better with a seatclamp and why did Time reverted to the collar a year later? Crack? Damage?
Many Thanks