Although it was produced in limited quantity for a few months only, the Atari 1200XL is common in the USA. Still, it remains much more difficult to acquire for European collectors like me.
Nowadays, I am still amazed by the timeless modern look of the XL series. An Atari XL (800XL) was recently included in a French auction of 2.000 objects with iconic design, ranging from Dieter RAMS (for Braun) to Le Corbusier (who was credited for a radio).
The superb Atari logo on boot up
Using 'PEEK' commands in BASIC to find out about the OS, Basic and GTIA versions.
For your information, the results are:
PEEK(53268) = 15 [NTSC]
PEEK(65528) = 191 [Not a 400/800]
PEEK(65527) = 10 [XL OS Rev. A, 1982-10-26, 1200XL (most)]
PEEK(43234) = 162 [Atari BASIC Rev. A, in external cartridge]