As with just about any firewall, Cisco PIX definately has some positives and negatives, in response to gold eagle I will list my personal feelings:

*Tech Support is second to none
*Price (especially compared to Checkpoint)
*Security (although it depends on the admin)
*Very Simple (as long as you like the CLI)
*Has just about all the same feature as any other FW

*Not really comfortable with the scalability in the Enterprise (When compared to Checkpoint)
*NO REAL GUI (I know I said one of the pros was the CLI simplicity, unfortunately, this is not good for users that are not good with firewalls, and/or have not used Cisco products) CSPM just does not cut it for most people...although it is getting better
*The PDM GUI does not work if the PIX config is over 2MB. Well...most configs are over in other doesn't work.

Bottom Line:
Very Very nice firewall that has several different products in all price ranges, and what else can I say...I have been a Cisco guy for a long time (CCNP, CCDP), and their products are great. I would say that the main weekness is the ability to manage a large number of firewalls easily across the enterprise. Best bet for your $$

I give it 4.5 stars