Anson, I ran the Speedgoat 50K this year, and I can definitely say it lives up to Karl Meltzer's descriptions: "...there is nothing easy about it" and "nasty terrain". His tagline on the t-shirt is "A Meltzer Designed Nightmare". Okay, so for a true trail runner, it's not really a "nightmare" because we all love the trails ... but Meltzer deliberately makes it as hard as possible. The terrain really is for the most part, nasty: it is technical and extremely steep. Along the way you climb a summit from top to bottom almost 3 times. So yeah, it is also very scenic - at least, if you can take your mind of the pain and effort.
I say all that to put it into perspective: I've done the Squaw Peak 50 twice, both the alternate "snow route" and the regular route, and I can say that the Speedgoat 50K feels just as hard in terms of overall fatigue. In fact the total elevation gain for Speedgoat is the same as the Squaw Peak 50, only packed into 31 miles. I would not necessarily recommend the Speedgoat as a first ultra. But regardless, you'll have to do some serious hill climbing training since the steepness factor is in fact MUCH greater than your average ultra.
That said, the feeling of accomplishment in finishing the Speedgoat is amazing, precisely because of the difficulty. Isn't that a big reason we do them? :-)
There's the Red Mountain 50K in April ... or the Antelope Island Buffalo Run 50K in March (http://www.backcountryrunner.com/trail-races/antelope-island-buffalo-run/)
I did the Antelope Island 25K this year as well, and I can recommend the course. It sounds a little boring, not being in the high mountains and having some repetitive loops in the longer distances, but I was pleasantly surprised. The Island is a nice place, with well-kept trails and scenic. It's a fast course, very runnable, and it's a great change of scenery if you've been running mostly on the roads or foothills during the winter. (Also if you find yourself not being able to train on hills as much, Antelope Island is a good fit because of the lower elevation gain for the race course.)
But for both of those you have to sign up early. The races fill up quickly.