Hydration Pack Trouble

I'm having trouble. Surprise, surprise!

After an extended comparison of various hydration packs, I believe I've narrowed it down to two options.  

On top is the Camelbak Ultra LR Vest.  The Nathan Vapor Wrap is on the bottom.  

NEEDS

• Space for storing extra layers.
• Storage for nutrition (gels, pills, bars, and sandwiches [i.e. something larger])
• A larg-ER bladder (1.5-2L)
• One water bottle holder; a second if possible.
• Easily accessible storage while running (no need to remove pack to get at nutrition).
• Comfort - easily avoidable chafing.

I believe both of the above packs will meet my needs, but I am concerned about A) the Nathan's side-zippered storage pockets rubbing against my swinging arms and B) the weight of the Camelbak being too low. 

I have a couple other reservations about both - questions I could answer easily if I had access to trying them on.  Unfortunately, there's no where in CT that I can find that carry either pack.  I'd either have to make a trip to Boston or just order them and send one back.  But I'm also looking into other packs by Salomon and other makers.  

Does anyone else have experience with or an opinion about hydration packs in general?  I'm all ears.

-----------------------------------------------------------------------------------------------------------------------

Questions
1.  Have you ever had to order a new piece of gear without having seen or tested it?
It annoys me and gets under my OCD skin!  I'm the type of person who wants to try it out and compare before putting money down.  

2.  Do you have any experience with Hydration Packs?  If so, what do you have?

3.  Any thoughts on what to think about for a 50 mile race and training requirements?
Am I missing anything key that you think I should know about?


DREAM.  BELIEVE.  ACHIEVE.