Jim, the tube they put in Parker is for the Mic-key style button. A Bard button is placed immediately during surgery and doesn't need the tube step. The tube helps the stoma heal so that the mic-key can be placed and removed. Because the Bard is a one-step process, it is harder to replace if needed. When Josh had his button flap break, he had to have the whole device replaced in surgery.
They call the MIC-KEY low profile because it is less bulky than a long tube, but the Bard style is much more discreet. When we were talking to our doctors, they offered us both choices and we chose the Bard for our active boys. I think at our clinic it is a "selling point" for pushing a g-tube.
My boys have been very active with their buttons in place. (Baseball, basketball, skateboarding, tennis, swimming, hiking, skating all gym class activities.) We have really found the only limitation to be cosmetic (like wearing a shirt when swimming).
I'm not positive, but I believe the decision about which device needed to be made before the original surgery. But talk to your doc about options.