I'm a first time Beardie parent and Smaug came from PetSmart. I would not actively discourage you from getting a Beardie from a pet store, but I would--based on my own experience--recommend getting your set-up in place FIRST. I know it's hard to wait 'cause you want some of the Beardie lovin', but set yourself--and your dragon--up for success.
This forum has great advice on what a good set-up looks like and, unfortunately for the newbie, it bears little resemblance to the BD "kits" on the market. As an example, I bought the Zilla kit and less than two months later the only things still in use are the tank itself, the water bowl, and one of the reflectors. None of the lights, not the carpet, not the food, not the gauges, not even the top. UPS was a daily visitor to my house for about a week and a half while I remedied the situation.
Second is to be on the lookout for problems. Five weeks after Smaug came home, he was at the vet with MBD, a skin problem, and a broken tail (as a result of the MBD). Have a vet identified ahead of time.
Third, know where you're going to get your dragon's food from. I ended up driving all over town trying to find the right size crickets, worms that weren't already dead, etc. If you're not able to drive yourself, really plan ahead.
My 2 cents (expensively gained...)
Smaug's Mom