I've been to the Alps 4 times and Whistler once - the first time we hired bikes - i won't do that again! and hence I've always taken my own since - The Meta 5 the last 2 times.
You just need to be sensible when packing it.
I bought the Tifosi bike bag (the thick neoprene type with wheels) - it was £100 at Wiggle but you can find them for as little as £60 now.
I made myself up some frame and fork spacers using some old 1" diameter alu tube cut to fit between the dropouts and some M8 'all-thread' with domed nuts to hold them in place - this makes it all nice and rigid. I take the rear mech off and zip tie it to the inside of the chainstay - and i remove the bars from the stem (Easy for me as i use a Thomson X4) and zip tie the bars to the forks. Cover the front of the frame and forks with pipe insulation before you tie the bars. Put something between the disc pads (folded old credit card etc) I leave the seatpost/saddle in place - just drop the height so it fits in the bag.
I then wrap my leg and arm armour over the stem and down the forks this protects the front and fills up the space in the bag which helps it keep it shape better.
The Tifosi comes with wheel bags - i put one wheel either side of the frame - I personally don't remove the discs - I just position them towards the frame, so far I've been OK.
I've been very lucky and have had no serious issues (tempting fate!

)
I would always take my own bike as hire bikes, especially in the Alps seem to be very well used!

Hope this helps
Simod.