Which CZ Lens for A99?

The af will work with the Sony, yes.

The bokeh of the Sigma is very good, comparing it to the CZ is splitting hairs, you're probably unlikely to see any difference in real use.

Here is a good review: http://kurtmunger.com/sigma_85mm_f_1_4_ex_dg_hsmid309.html

Here is a random photo of a cat http://www.flickr.com/photos/f_l_e_t_c_h/7823285720/

Nice creamy bokeh, you're not really going to find a 85/1.4 with "bad" bokeh.

I think the general consensus is the Sigma is a little sharper in the center wide open, while the CZ is sharper in the corners and stopped down.