The StudioEE is in fact a 500 body (they were marketed by many names...) - the only thing that differed was the stylus.
The AT960x is an AT10/11 by any other name (and AT sold this body by many many names!)
It can be fitted with anything up to an ATN12s / ATS12s shibata needle (which are very nice tapered cantilever with a high quality shibata on the end) - and the Shibata styli can be picked up for around $50
http://www.turntableneedles.com/ATS12S-Needle-200-DQX_p_3802.html
Depending what needle is currently fitted to the AT960x it could be anything from a spherical/conical to a shibata.... What colour is the stylus mount?
I think the AT has the greater potential...
Bye for now
David