If I sell Pioneer/buy Aries, hear BIG difference?

At the risk of repeating what was said before, the difference will be dramatic. If it isn't I will come to your house and eat the Teres and buy you a new Pioneer.
Everything about the sound will be improved. You really have no idea what is on your LPs if you have been using the Pioneer. That is not intended to be a rip of the Pioneer as much as it is a compliment to the Teres.
The only question you will have after listening is why you waited so long.
Personally I prefer Sota TTs though.

I agree with the above posts. However, you will not hear most of the difference if your preamp and rest of the system is not up to the same level.

Well I DID IT!

Got a used (audiogon) Aries extended w/JMW 12.5.

Still setting it up, and am waiting for Symposium Ultra platform to put it on....

Thanks, guys.

Good for you!!! You won't be disappointed. It's amazing what is really hidden in those little black grooves. Let us know how you like it when it's up and running.