I've had a standard rise one but all our others have been high rise, I much prefer the high rise ones. Also means they'll last longer, particularly if you have a long baby like mine! He outgrows everything in the rise first.
Double fabric means one fabric at the front and a different one at the back (so you could have 2 different colours, or some people like the cotton print fabric at the front and the minkee at the back, etc).
I personally prefer the sized side snap ones rather than the one size pockets, we don't get a great fit with the one size pockets. Everyone is different though, others prefer the one size ones because they last longer so they feel it's better value for money. Whichever you go for, I would definitely recommend trying out a preloved one (or see if someone can lend you one) to see if it fits nicely before you splash out on a custom one.
I love the idea of the AI2s but unfortunately we never got on with them, both of mine are far too heavy wetters and they just don't last. At least with pockets you can stuff as much absorbency as you can in there.
Have a look at the Weenotions Facebook page, lots of lovely pics to drool over
also this thread has lots of pics: viewtopic.php?f=9&t=72744