Wowser! If we are comparing amount of expert/advanced terrain at one loley resort, Jackson Hole versus the whole of SLC's 9 resorts, how can you possible even compare, it doesn't.
JH claims 2500 and I guess backcountry is now open, so we can add something to add. Look at the JH trail maphttp://www.jacksonhole.com/info/mtn.maps.asp
Understand that the entire left side is the Hobacks. Both times I was there in February it was hard, very hard death cookie crud in the am, and turning to slop in the afternoon sun. i am sure it is a powderhounds dream, !when it is snowing! Hobacks represents a good chuck of terrain.
Now it is quite good fun to ski down 4000 ft of fairly steep verticle and I recall the tree skiing is just right. But you will find youself skiing alof of the same stuff if you plan on skiing there 5 days(+1 Targhee). I remember skiing many of the same chutes again and again. Something I never do at Snowbird, never.
compare that Snowbirdhttp://www.snowbird.com/ski_board/trailmaps.html
which I think is equal head to head for amt of expert/advanced terrain as J-Hole. Then you have Alta right next door, plus 7 other resorts, all of which are big and bad! And each of them has plenty to keep anyone busy for a good day.
For a week(6 days) though, a dream trip would be to ski 4 utah resorts, drive up to Jackson, ski there for 2 days and back down to the airport to catch your flight back out.
I do give Jackson all the scenery points and apres skiing though(except top of the bird beats all), it is a very nice part of the country, even if it has been taken over the last 10 years, (by the rich and outsiders), yellowstone is right up the road, you can/will see elk right outside of town, there are real cowboys around, and the town square has elk racks forming an archway. and of course there is that what is it? mangey moose bar or something? and a "real" steak is quite easy to come by.
don't even think about comparing the whole of SLC for a week
! to J-hole regarding the skiing.