The hook and loop fastener with the opposite type on the instruments allows me the freedom to easily move the instruments around or borrow and try out others. The straps allow security and an ease of adjustment that I'm very happy with. There are well placed loops to take the lanyards you should to have on your instruments for simple back up.
The straps on the back of the flight deck go round my chest strap, and the ones on the sides loop through the carabiners, offering a large range of adjustment of the angle that the instruments sit at. For ridge soaring and basic flights, I leave them fairly slack as I only need to see the altimeter and some basic information on the GPS.
When I'm flying XC or in a friendly competition, I adjust the side straps for exactly the right viewing angle for the third instrument which has the competition task on it.
The flight deck has more than enough storage for all the smaller items you will be using. I keep spare batteries, a power pack, spare mobile phone and the competition tracker in here when flying. It's also a great place to keep all these things, as a last minute battery change doesn't involve getting out of the harness.
After I've landed it's the best place to keep all the small items I'll lose, including my cheap 2m radio. I put it in the glider bag, and it protects the stuff I'd otherwise damage in the bag. Having a flight deck that can easily fit in my bag prevents that horrible problem where you put it down somewhere and then go home without it.
I have now had it eight months and I'm very happy with it. It will take two small instruments and a large instrument at the same time. I therefore recommend this as an item very well suited to its job, robust, and easy to use.