Yannick,
I played Lost Canyons Sky one time. Somehow, I missed Rustic, so I can't be dragged into the debate of the relative merit of the two. I found the Sky course to be challenging, entertaining, visually attractive, and fun to play. All good. But, it can be punishing and you will probably lose some balls, but that to me is just a trade off for the good.
The day I played, the wind howled which makes it doubly challenging. I suspect the wind howls much of the time there given its location. And, yes, it is on a difficult piece of land that does not lend itself to walking. And, yes, it could be a rough ride for a high handicapper (say, over 14), but it is some ride.
As an eastern Canadian flatlander, I find the mountain courses entertaining and different from what I'm used to. I also don't understand the concept of giving it zero play if you're in the neighbourhood. Not all the holes may be great, or even good, but it's well worth playing just for the experience of a different sort of course. And, the visuals, the green complexes, and some of the holes make it a worthwhile experience in my opinion. And, at around $100 it's not out of line with many US courses price wise. Rustic, at $50 sounds like it is unusual, in my experience, as far as US prices go.
Here are some additional (non-professional) pictures. How can anyone not like these holes, at least once?
The short uphill 1st. Dead into the wind. Hold on to your hat.
Somewhere around the 3rd or 4th. A double dogleg par 5. Visually intimidating tee shot. There are many places to lose balls, but it's no worse than having a lake on the inside of the dogleg.
Somewhere around the 11th. An uphill semi-blind tee shot. Not for the weak of heart. Followed by this second shot. Death to the right, bailout to the left; and what a backdrop!
The 17th, par 3. Do you have the balls, literally and figuratively, to go for the back left pin? Or, bail out to the right. And, the green, irc, runs to the back and left. No easy chip from the bailout.