I own Ozone C4's 2012 (5,8,10) and I weigh 55kg so about the same as you.
I can use the 8m from 12knots but the fun starts when it's around 20 knots.
The bar pressure is good and it has settings for a higher bar pressure.
For kiteloops the C4 is really good, it's a quick kite and the pull in the loop is good.
I think the wind range of the C4 is great, I can use the 8m from 12knots and when it's 30 knots or more I use my 5m , I once used the 8m in 35 knots but that was just because the wind picked up and I had to go back up wind, but I was surprised that I could hold it

.
Unhooking on the C4 is good as it was made for freestyle. ( My level in unhooking isn't that high, I can do a railey, s-bend and railey to blind.)
It has a nice hangtime and lift, so big jumps isn't a problem.
The quality is (almost) perfect.
Relaunch is super easy, just pull one line and it flips over.
The safety... I like it because it's simple and easy to use, but there are many people that don't like it because it isn't a Push Away system so it's maybe the weakest point of the C4.