Does anyone have one of these yet?

I guess my question could apply to all backpacks.

For the past 4 months have been using a pac designs ultimate. Really like it, very comfortable on the bike, design of the bag is top notch and has all kinds of cool pockets and places to put things. My only complaints with the bag was that really large loads are very cumbersome, walking with the bag wasn't so good. Also have been getting some neck pains lately.

Ever since I saw the reload flight pack in the reload blog, wanted to try one. Especially when I had a huge load in my shoulder bag, trying to raise it above my head, would think how nice a normal backpack would be right about now. Finally broke down about a month ago and ordered a large custom flight pack.

It came last week and have been riding with it for a few days now. The bag is extremely comfortable standing or walking, but when on my bike it feels really strange. Like it's constricting my movements, or pulling against me in a weird way.

Anyone here went from a shoulder bag to a double strap and experienced this? Maybe I just need to get used to it since have been riding with a shoulder bag for a bit? Or maybe the bag and my body just don't match up?

It's a shame since this bag is really nice otherwise.

Let me know what guys think. Thanks.