<p>Did you ever have to choose between WISA or LAMP at the beginning of a web project?</p>

<p>While pros and cons are littered around the net, it would be helpful to know about your real experience in coming up w/ criteria, evaluating, deciding, and reflecting upon your decision to go w/ either platform.</p>

@Thomas WISA is:
W=Windows
I=IIS
S=SQL (Microsoft SQL Server)
A=ASP (or ASP .NET)
As for choosing between them, I would think that the available resources and talent would be the deciding factor. If you can get great ASP .NET and MS SQL devs, go that route. If you've got a bunch of PHP/MySQL gurus on hand, go LAMP.
The reality is, regardless of the pros and cons of the platform, you'll struggle to get a great system on WISA out of a primarily PHP dev team, and vice versa.