Hi Quaddawg,
Sorry I have taken a while getting back to you.
SAS - A well set up SAS front end gives great articulation. SAS is not always stronger than IFS - that is a mith used by SAS freaks who do not know better. Remember that even SAS set ups have weak examples. Birfields - there is a belief that Birfields are weaker than UJ set ups - BULL SHIT

We have guys over here running Nissan front ends with 4500lb rigs running 300hp motors with plenty of torque, open and locked ( ARB in or out ) and 35" aggresive tyres ( Simex, Boggers etc ) and the Birfields take all the punishment they recieve. Interesting to note though that the OE Birfields are stronger than any aftermarket offering

IFS - These can be built strong - Nissan, Toymotor are good donors for upgrades. My old Nissan 720 had IFS with a welded diff and ran 31's ( big for back then ) and took a pile of abuse and never failed once

IFS Advantages - you can get way more clearance under the cross member than SAS ( when using the same sized tyre ) - really handy when running through deep ruts ( which we do a lot over here ) and the space between the tyres is very clean ( no obstructions hanging down ). SAS set ups tend to "drag" the diff through the mud instead of sitting above it ( ala IFS ). It is always easier to get through something if you stay above the crap instead of trying to push your way through it.
There are heaps more pro's and con's so maybe we should start a new thread and really get people fired up.
ZeusZuki