The SPIbelt is a pretty nifty piece of gear.  I first found it while picking up my race package at the expo for the LA Rock n Roll Halloween Half-Marathon.  Having been born in '83 and growing up predominantly in the 90's, I saw "fanny-pack".  This item is not cool and I would never use it.
They say a fool and his money are soon parted.  Well, with God as my witness...I AM that fool!  I fell for the old "we're closing and I'll give it to you half-off after a military discount" trick.  It turned out to be one of the best dumb decisions I have ever made!
There were a couple instant advantages.  I could fit the keys to my Jeep, my ID, and my cell phone inside.  This meant that I didn't have to run with the key tied into my shoe, my ID inside my compression shorts, and the need to hold my phone in my hand as I used it for music, pictures, and race tracking with Endomondo.  It would have been worth it with that alone, but the belt also came with an integrated bib holder and elastic bands to store energy packets.  Best of all - its incredibly streamline and hardly noticeable.
The only issue I had to figure out is "how would it run?"  Before I finished that 13.1 miles, I had the answer and I was hooked!  There was some movement when I wore it in the front, the way it was presented in pictures.  It annoyed me a lot, but once I twisted it backwards so the clip was in the front and the pouch was above my butt, it fixed everything.
Are they durable?  Well, after two years, miles of training, day hikes, three Spartan Races, one triathlon, and a bike marathon it is still holding up nicely!  I even picked up another one before the Pasadena Rock n Roll to lend to training partners.
Would I recommend it?  Absolutely!  But, get yours quick because the company will probably go out of business for making a product that is just too good.  You'll buy one and it will last and last.
Happy training!