The Shiner GASP is a great ride, I did it last year and might do it this year. It is a big ride so you will have lots of company and the support is great. Expect a headwind to Shiner, sorry it is the truth this time of year. The course is mostly rolling hills, if you are riding 360 they will not be anything to be worried about at all. Roads are generally pretty good, although I remember one fairly long section of chip seal.

My number one piece of advice- plenty of time in the saddle. Last year I had been really busy and logged a low number of miles, the ride was way harder than it should have been.