Thanks!

I think the brown one is probably my favorite thus far, and according to Panerai guys, the Dirk straps are as tough and as waterproof as they get, so we'll see. To be honest, I heard so many inputs on straps that I figured I'd buy about 30 of the most popular ones (with an OEM Breitling as a reference/control) in a variety of materials to see which ones I like most, and ultimately keep some and sell or trade some. Thus far, most of the makers I have bought from make a great product and deliver excellent service.
Shark has a smell that is somewhat different but I'd still call it a bit leathery. I think whatever the smell is it is from the treatment and dyes they use on it.
About half of what I've ordered thus far has been shark, as supposedly it is the strongest of all leathers we use...and oddly enough, the shark doesn't get that deformation/imprint from the tang buckle, and yet it is butter soft and flexible unlike some of the reptile straps.