I've noticed after checking various places online and also at Ostores/vaults and it seems like there are two versions of the Unobtanium band. I've seen a few that look flat and smooth (similar to the leather band) and I've seen a few that have vertical "valleys" that run the length of the band. Can anyone confirm this for me?

The flat and smooth Unob band is the 1st gen and is now discontinued, it is much better looking than the 2nd gen Unob band with the valleys on it, IMO

I have the '2md gen' version with the long valley's in it and feel it gives the band a bit of character and makes it different than the flat/smooth one. There is a slight texture to the flat one and it very closely resembles just a leather band, I dont have anything against the leather but if I wanted that look I would just get that one. I love the sporty and aggressive look/feel of the new rubber band, it gets just as many compliments as my TI bracelet.

The 2nd gen band also has the lettering in top near the case which to me is distracting. I like the original best and have a stash of spares since it is out of production...I need a brown leather one too since it also is done and oop.

Yeah, I wouldn't mind tracking down a spare brown leather band so I can have a spare. I just managed to track one down, but I wear it, so having a backup band would be nice!