That tire looks about 50% worn. I've never experienced the RS3s heat cycling out in the 2 sets I've worn down to the cords. They've been good until the cords are about the show. I just corded 2 fronts this past weekend and I was only 1-2 seconds of my pace.
I would hold off on R-Comps unless you are comfortable sliding the car. They have more grip but when they let up its a lot more abrupt so anticipation is the key. from what I've read, NT01s are not recommended for wet driving so you would likely need to swap tires or bring an extra set. For me, the extra second you MIGHT get from a R-Comp just ain't worth the added pain of bringing MORE crap to the track, MORE work to get your car ready, and MORE money because those NT01s won't last nearly as long as those RS3s.
A silver E46 ran NT01s this weekend for the first time and we ran just about the same lap times. We usually run really close and he might gain a little bit on me once he gets used to the NT01s. The difference was when it rained, he left and I stayed and ran 2 sessions. Or he could have stayed and changed to street tires in the rain...just saying...
2015 F34 328iX GT Glacier Silver
2011 E90 M3 Monte Carlo Blue
2004 E46 M3 Imola Red