differences between CLS models

[zaphod]

there are about 5 differnt models of the CLS (1, 1A, 2, 2A, 2Z, anniversary and so on). i have heard that the Z models use transformers that are not available anymore, and I am sure that there are some sonic differences between models.

is the rumour that the Z transformers are no longer available?

can anyone comment on the sonic differences between models?

thanks. i'm trying to decide whether or not to buy the CLS 2A currently for sale in the classifieds area instead of just getting a panel upgrade on my current CLS (which i believe to be CLS 1A).