There is a tri version of the saddle, the TriAthgel. trisports.com sells it.

There aren't cut-outs <i>per se</i> on the saddle, but there is an area that's a bit scooped out, which does help for those times you're in the drops. I still try and keep scooted back so my sitz bones are supporting me, though.

I've never tried the Vitesse. When I bought my Aspide Glamour I was deciding between it and the Vitesse. Since I was concerned about rubbing on my thighs, I went with the AG, and I'm very happy I did.