First, I'm a civilian and never considered military service until I was too old and too entrenched in a satisfying career (with an aspect of "service" in it). When I was younger, health problems would have kept me out. But I did some research on the Texas State Guard, and granted it was in a pre-9/11 world (but not by much), and here is what I learned:
Think "state-based citizen militia", which is very different from a "federal standing army" and its reserve units. It is a bit of a shame that their name implies a connection to the National Guard, their uniforms are essentially the same as the "regular army", their gear is basically NG cast-off's and that they drill at NG facilities. If they would differentiate themselves a bit more, perhaps they would appear more legitimate as what they are. Having said that, I spoke at length with some folks... one was a Gulf War Vet who had gone NG-Reserve and was a co-worker of mine. His impression (from interactions during his NG-reserve drills) was that they were beer-gut wannabe's. Another was a state guard member, and he said they mostly do honor-cordon's for the state of Texas... but the way he presented himself was a bit of a put-off, as he fit the 'wannabe' perception in my mind.
However, with the War on Terror in full swing, regulars, reserves and NG units are stretched thinly, and surely the State Guard is utilized a lot more. I've kept them in the back of my mind as an outfit I could join if the SHTF and the need for long-term homeland defense outpaced the supply of folks who were better qualified than I.... sort of a "career path" for me from member of the "unorganized militia" to the "organized militia". I really wish, though, they had better PR.