Congrats!! If you can do a movement swap, your 21j PO will last a loooooong time. If the movement dies, quick swap. The ETA version will be maintainable by any watchmaker.
I find the AT CD series a fantastic watch and one I wear almost all the time. The Hublot has more bling factor to it, and a more in-your-face design...so figure out which you would wear most depending on the circle you are in the most (work, social, etc) and get that. If in doubt...get both.