Depending on what you use it for, a piston may or may not be what you want. A piston system will add moving parts, and add weight. Some are less reliable than others. They add about 300 to 400 bucks to the cost. Most of the drop in piston systems are as simple as changing the gas tube, a couple of others not so much so. Those require the skills to change the gas block, which may not be an easy feat, depending on your skill level. Just some things to consider.
"Democracy is two wolves and one sheep voting on what to have for dinner.
Liberty is the well-armed lamb contesting the vote." - Benjamin Franklin