No point in having one with a dual ring up front as said above, you lose most of the benefits of having hubs gears if you run 2 rings up front. Besides, if you need the extra gear range, just stump up the cash for the 11spd version.
As it is, the 9spd Alfine is a very good bit of kit. It has its faults, but overall it performs respectably as an offroad, or even commuter hub. The gear ratios are a little wide-spaced in parts (namely 1st-2nd and 5th-6th), but I used to ride mine in 5th pretty much everywhere offroad, and use the lower gears only when really needed (using it like a Singlespeed with bailout options), and 6th and above for DH or onroad riding.
I'd have one again, definitely, especially if it was purely for a bike to deal with the winter slop. But I'd probably go for the 11spd version now it's available, the wider range (equivalent of 2x9 setup) would be welcome.
And despite what the nay sayers say, the "extra" weight isn't really all that much, OK it's concentrated in one place, but it really doesn't add much weight to the bike. The bike will feel a little more rear end heavy than it did before, but its certainly no biggie.