Which version would you prefer, and why: the Pilot in command version by Wilco from 2006, or the 800/900 version by PMDG, from 2004? Both version got very good reviews at Avsim
.
http://www.avsim.com/pages/0206/737PIC/737PIC.htm
http://www.avsim.com/pages/0504/pmdg_737ng_review/pmdg_737_review.html
(The PMDG boxed version meanwhile sees the 800/900 delivered as a standalone product, no longer as an upate for the 600/700 version, as the Avsim review states)