Kind of a quiet Thursday theme today, with six answers using XSANDOS symbolically, as revealed in 38-Across. Boy I used to hate hearing THREEX[times]ALADY (3D: 1978 #1 hit for the Commodores) on the radio when I was little. I never really liked the expression X[kiss]MYGRITS (5D: Sitcom catchphrase of the '70s and '80s) either, but I do like the use of an X to signify a kiss (see also BEARO[hugs]S), so I'll give that one a thumbs up. And O[zero]SUMGAME (39D: Situation in which, on the whole, nothing can be gained or lost) just came up in a training session I was in yesterday, so that's kind of interesting. To me. :) And finally, 26D: Went back to where it all began (TURNEDFULLO[circle]) makes us think again of Inigo looking for Vizzini in "The Princess Bride."
1A: Abbr. before a date (ESTD) - D. I think we've estd. that we dislike abbrs. at 1A.
Favorite: 44A: They'll make your hair stand on end (GELS). Ha! (runner up: 28D - ESSES)
Least favorite: 33D: Vessel opener (STENT). Eeewww.
I had never heard the expression "31A: Freeboots" (MARAUDS) before, so that was fun, and everybody loves TUNASALAD, right? I think I must have heard "Fluctuat nec mergitur" before, but I was sad that I could not come up with PARIS until I had at least two crosses. Hmph.
Overall, I enjoyed the cluing in this one, and there were a few VIVID entries without being too LURID. Fun theme, so... thumbs up.