I haven't tried PATS yet but for my options and futures portfolio i am testing a new site called RiskBox. it's got a really useful gui for managing my portfolio on Liffe and Euronext options. It covers US exchanges as well so it's worth a look while it's still on free trial! You can sign up at http://www.riskbox.com and have a play with it!
I found it really useful so far, it just doesn't include execution yet
Out of all the things on the net, I haven't seen anything which is as integrated with as many functionalities: VaR, stess testing and more on my portfolio in real-time. I have a friend who is just using it for his spot FOREX and running P&L on that as well!