The 75L Bigkit was bought to replace my 57L Thule round trip boot backpack for skiing. So much more space it's much easier to pack now. I can bring everything I want (including my downhill boots) and fit my Kamber 22 skiing pack in it as well! One huge difference from other ski packs is the boot compartment, there's a drain and the boots face sideways not out, keeping the weight closer to you and easier on your back. Very comfortable. I use it to lug my mountain biking stuff around too. So the interior water bottle pouch is very handy. Only one con, the goggle pouch isn't crushproof. Highly recommend.
Zach the outdoor addict