Kinda depends on what ya wanna do off-road. If it's rock crawling or mudding, SAS is the way to go. You get more articulation (suspension travel) from a solid axle and you don't have to worry about CV joints breaking.
If you are just riding trails, going in snow or sand, then IFS is completely suitable. Some drivers will state that IFS is quite a bit better on washboard sand than a solid axle.
Others on here can certainly give real-world testimonials. I haven't wheeled a solid axle since about 1989. I only purchased my 92 model 3.0 4Runner about 2 1/2 yrs ago. It still has IFS and that's the way I want it. I'm not a mudder or a rock crawler. I just like it for winter transportation.
Mike in AR