for a beginner yes it is good for the price and the bike is not bad itself. make sure there is no major damage. take a friend that does ride with you to test ride it before you purchase it. protect your interest at all cost.
I don't really know that this would be a con, especially if you have not ridden yet, but just remember that lowering will affect the handling of the bike. I guess it will mostly be up to you whether this will be a con or not, but it will reduce ground clearance and lower the center of gravity.
with it being adjustable i figure if i want to go out to the twisties ( when i get better, of course) than i can leave it at the stock setting and if im just going to work or sumtin that i can lower it
wil going form stock heighth to 3'' lower will it mess up the shocks?