Perfect Flight airline (especially BA) simulations???

What is the general opinion of the Perfect Flight (www.fs2000.org) airline simulation series? They have done Northwest, United, Lufthansa, and most recently Speedbird, which looks quite interesting to me. It seems to offer quite a bit--more realistic planes (are they any good?), flight crew, ratings, and so on--within a single and reasonably cheap package. Yet I've never really seen any discussion of this series on any of the websites.So, does anyone here have any of these airlines? Would you recommend them?Thanks.Marc