buying an Tele-Tessar for my SL66?

Hi folks,
Recently I´ve seen a Tele Tessar 500/5,6 (non HFT) in a dealer´s store,
price was about 1000 Euro (greetz from Europe), too high for me.
Now it dropped down to 700, and I think about buying it for my SL66.
Is there anyone who uses this lens? How about the optical performance and
color rendition?
best regards, Slixtiesix