I have been using an Ursack in the Rockies for 3 years now and I love it. I am very confident it is puncture proof from a bear but I do use the Opsack (the odor proof ziploc that pairs with it) as well to eliminate odors. I find I get an average of 10 trips out of an opsack before it rips or needs replacing.
I am usually hiking with a 50L bag and find that canisters super awkward. Now I will only use them if a US national park explicitly tells me I cannot use the Ursack. Even then, I did argue with the rangers at Tombstone that it was allowed under their written rules...
I like it because I don't need to find a hang for it and can just tie it to a tree or large rock. If there are no rocks big enough then I will bury it in pile or rocks. Works well and I have yet to have a bear come poking around at it even though I know they have come through camp on at least 1 occasion.
I wouldn't bother with the Aluminum insert, most backpacking food is relatively crushproof anyway.
Only downsides is that it can get kinda soaked if it rains or snows heavily, but it does dry out quickly. Also, it is useless as a seat when eating
I bought mine at MEC and I believe it was a fair bit less than $130 US.
Edit: Yup they are alot cheaper.
10 L is $99 and 15L is $115
I have the 10L and find it good for 2 people for up to 3 days. Might look at getting another or getting the 15L myself (don't think they sold that one when I bought mine.)