I live east coast and have always rented skis for my trips out west (and I actually have wider skis here at home):
1. You can't be sure of deep stuff out west, regardless. You may actually want narrower skis.
2. If you rent and do want wider skis, you can decide which width/type to rent...and then re-decide the next day depending on conditions, and re-decide the day after, etc., etc.
3. If you rent, you always get new and different skis. You could go new-style 5-point skis, wide carvers, etc., etc. You are always up-to-date.
4. Renting for a week for 5 years is still cheaper than a really good pair of nice skis and bindings. I spend about $25/day b/c I reserve very early and aggressively seek out bargains.
5. If you rent, you skip the hassle of shipping/carrying skis. I take my boots, rent skis, and never have to worry about how they will be treated by the airlines. Travelling easier is worth something to me.
Conclusion: rent where you ski. It's easier, cheaper, more satisfying, and...you get a variety of experiences rather than being locked into one pair that you own.