Writing a review here because so far there's only one other review I've seen online, and in that review the reviewer complains of unacceptable heel slip. I just received these shoes (gold/black color, size 45) and have put 150K on them. My previous shoes were Sidi 6.6 vent carbons (white/black vernice, size 45.5) that I bought in ~2013 and are still good, but the white parts are starting to look a bit dingy. My old shoes have the heel retention device and I was a bit concerned about heel slip with the 60s, but this hasn't been my experience. The shoes are much more comfortable and slightly lighter, and I think the heel cup is designed better. The toe box is a little roomier than my old shoes; even at half an EU size down, these shoes feel slightly bigger (in a good way) and, as mentioned, heel slip hasn't been an issue for me.