The GSA PRo has both merrits and deficits.
July 23, 2014
I do most of my practicing in the garage using "Almost Golf" golf balls. When I initially used the GSA, I was obtaining club head speeds and distances which were only ca. 80% of my actual speeds. I had sent messages via e-mail to 3Bays but they did not reply. I subsequently discovered after much research that using "real" golf balls will afford the correct speeds. I subsequently called the 866 number and the individual was very helpful and confirmed my results. As it turns out, the e-mail address they afford goes to China and it is very unlikely you will hear from them. It is better to call 866-661-2340 and get a US rep who seems to know something about the unit. The biggest problem I am having right now is that the program locks up during the processing mode and I can't get out of it without an uninstall. I have had to do that 3 times thus far and, as expected, you lose all of your old data. However, the GSA does have merits. It gives you a profile of your swing and, if you can figure out what you are doing wrong, it will definitely help you correct your errors. It shows you what is wrong but it may take a Pro to help you correct it.
Pros:Swing profile. Relatively accurate club head speeds and distance when real balls are used.
Cons:Program locks up in the "Processing" mode which can be irritating.