Tokyo Marui Sig P226. There are lots of good postols out there, KSC and TM being at the top of the pile, but that's the one. That being said, "lifetime" is a bit extreme. Postols by their nature are hard on themselves with so many small moving parts constantly rubbing against each other. So maintenance will play a part, keep it clean, keep it lubed, etc. Plus upgrades and replacement parts are available, so you can repair little things that do go. Stay on it and you can get ten plus years out of it arguably, but your average pistol has a four to five year shelf life, if used a lot.
I have developed a new sport called Airhard. Pretty much the same as Airsoft, except you have to maintain an erection...