Well, my 4.44 is a transmission and rear diff from a 1998 Forester. I have an SVX diff to swap in there soon, swapping the ring and pinion to maintain the 4.44 while getting back the limited slip diff. An SVX without a limited slip diff is a handful in fast corners
The advantages? Well, much quicker off-the-line acceleration. Plus, the Forester transmission seems to be able to handle a lot more punishment than the tranny that was stock. It's pretty much a bolt-up replacement for the stock tranny and gives the car a very different character.
Like everything though, there's a trade-off. At the top end the car runs at higher RPMs on the highway. That means that the SVX loses some gas mileage. So far my best has been around 22mpg, and I average about 19-20mpg in mixed driving (90% highway). Whether this is a bad thing or not is really a personal thing, but the increase in RPM also means an increase in highway noise. If you like your SVX being a calm, quiet highway cruiser then the 4.44 is probably not for you.
I've been thinking of taking the 4.44 out of my SVX and going to a 4.11 possibly 5-speed. While I like the extra off-the-line punch, I think the 4.44 may be a bit too much for me. Then again, maybe not