The single biggest reason I went with the 3130 was the skid steer QA loader. I want to change between a forkset and the bucket. I would have gone with the 3400, but by the time the after market pieces were added to the loader, I could get the 3130 for a few bucks cheaper since they have a larger rebate than the 3400.
I loved the JD790. It is nice and compact, yet I'm 6'2" 220 and I didn't feel cramped in it. The price difference between the
L3130 and the JD790 was $1650 (after rebate). I felt that it was worth it.
I'd suggest you buy what feels best. I have a neighbor who gets by just fine with an older 2wd JD850. He added a bush hog loader to it and he was still under 10k. He has been hung up a couple of times, but we are in an area surrounded by swamps. If your main use is going to be maintaining a large yard, and don't expect to be in soft areas, save your money.
One thing I found is you get into the "it's only $1500 more" game. Well, soon enough those $1500 additions jump you into big money.
Good luck with your decision. Let us know how it goes!