This question is right in my wheelhouse. My wife and I had season passes to Brian Head last season and have been 3 days this season. There should be ample snow when you are there, that's arguably their best time. That said, there's a reason my wife and I drive 6 hours to Salt Lake from Vegas several times a year.
What are your goals? Mellow cruising on great snow with awesome views and no crowds? Brian Head is great. Dropping cliffs, chewing up 2500+ vertical per run, attacking the steeps, seeing some of the best skiers and riders doing their thing? Salt Lake is the place to go if you are good and want to be challenged.
So if I were you, I'd think about what my goals are. Personally, I like to challenge myself every time I go out, and Salt Lake will do that. If that's your personality, your legs will be burning at the end of every single day you put in at SLC, but you'll be smiling the whole time.
On the flip side, there is something magical about lapping the Dunes lift on a powder day at Brian Head, no one around you, no sound except the whisper of your board, drinking in views of Cedar Breaks and the Tushars in the distance.