I got a bit bored last night and started playing around with the YOTS Prime and Omega. Combined them with the Energon versions. My Energon Prime kind of sucks, I can never find a complete one for a good price.
Energon Prime and YOTS Prime
Wing Saber flight mode + YOTS Prime
Wing Saber battle mode + YOTS Prime
Energon Omega + YOTS Prime
YOTS Omega + Energon Prime
Left half Energon, right half YOTS
Right half YOTS, left half Energon
My opinion on the lot;
Energon Omega, better colouring overall, head is better, still has the lights and sound, like the detachable head function. I paid $112 (2006?), Worth it? Hell yeah!
YOTS Omega, heads a tad out of proportion, like the flip up visor and the new claw, colour could be better and no lights or sounds. I paid $99 (Amazon)
Worth it? Somewhat, it's not like an "OMG I WANT IT!!1!!" more of a "OOOOH SPECIAL ED!"
YOTS Prime, Love the colour, more flamboyant than the Energon one, does NOT go well with Wing Saber, colour scheme wise; mine was flimsy, windows are loose, left one comes off easy and his gun doesn't catch easy and can randomly fire. I paid $79 (Amazon, + 40 shipping with Omega, totalling at 220) Worth it? Yup, never had an Energon one as a kid, I say close enough, cheaper than the original too.
Energon Prime, Seems of a better build quality, it has weight while YOTS is hollow, personally haven't tried the sounds yet, so can't speak on that. Mine never had a helmet or a gun and it seems to be hard to him them complete for a decent price. I paid $44 (Ebay, incomplete) Worth it? Here and there I guess, just needed one for the collection and YOTS' weren't announced yet. A complete one was around $100 shipped and I didn't have that kind of $ then.
I hope they do and Energon Wing Saber or Armada Prime w/ Jetfire and Overload for the upcoming ones.