Nice Job. The stitching is very nice as well.

One thing to consider before going with non-adjustable straps is that if you only wear one style of kilt ie. 16 oz. wool with a traditional high waist you can get by with a non-adjustable strap. But, if you ever wear a PV kilt with a low waist, or even a Acrylic kilt with a high waist, your sporran will hang a bit lower. This is where the strap needs to be adjustable. Between my PV kilt and my Heavy wool kilt I will adjust my sporran strap about 3 inches.

But really you are not comparing Apples to Apples. Don't get me wrong, I would never insult your craftsmanship, however, what you have there is not what could be purchased for $32. Actually, what you did there for @ $15 would fetch probably about $20 from some online vendors.