Hi Oakiris:
I'm upgrading my teres from 245 to 255 as we speak. So, I can share my thoughts on the improvements. Chris at Teres was kind enough to offer sending me the new platter before I send the old one back, so I can do before and after comparison. Should be fun. He's also sending me the new record clamp too, to see improvements there. Finally, I'm upgrading the motor and going for battery power too. All told, I expect to see a nice improvement.
I haven't heard the 265, but a few thoughts kept me back from pursing that purchase. For me, all that wood just looks a little old/vintage for me - wheras the 245 or 255 has a bit of a more modern look - just a matter of personal taste. Then, from reading other people's impressions, the upgrade from 245 to 255 appears to be more of an improvement than that of going from 255 to 265, and the price of the 255 upgrade is much more cost effective than going full out for the 265. Finally, I've read in at least one thread that some few people prefer the sound of the 255 to 265 (I think the point that was made was more resolution with the 255 compared to the 265 which had a more natural presentation). So, 255 seems the right way for me. Still, despite what I say, in the future I might sell the 255 and get a 320 - that table just looks great (despite all the wood) and looks less imposing than it's larger siblings.