Can I just say cheapestnatostraps.com are probably my favourite strap seller.
I've got at least six of their straps, with two more and a couple of watch pouches on the way, and I have to say I'm really impressed with both the quality and value for money. Their elastic straps are really comfortable, and the material is on a par with Erika's Originals straps. I even think, while it might be less robust than the stuff she uses, it's softer and feels nicer on the wrist. Oh - and the sheer number of colour options is great. I haven't seen any other seller with as many options, especially for elastic straps.
That's not to say they're perfect - I have two small niggles with their products - the hardware on the Paratrooper straps might be a little on the flimsy side, as I managed to dent the buckle bit it hooks on to, and the RAF straps have wayyyy too many holes, which is annoying when you glance at your wrist and see a track of holes running up the side of it. But the former might be a non-issue, seeing as I'm pretty sure I did it while climbing and it might have damaged just about any buckle.
Was interested to hear others' thoughts on them and your experiences with their stuff - particularly their watch rolls, as I've been tempted to buy one of those...