Purchased two AGI & RSST, AGI looked great at first but regret I bought them, voltage drop, center spring so thin that mine are now welded together and blackened in center, seems AGI can't handle higher currents, has tiny meshhole and it's threaded, you'll have to make really thin wicks on AGI, bottom plug screws have a really loose fit so might leak in dripper mode, mine leaks inside my center tube as well, fiddly to setup and negative deck screw is placed to close to the mesh hole.
RSST, exellent atty, I get much more vapor and heat, easy to setup, looks better, I got nicced out with RSST so needed to adjust my juice a bit.
No spare parts comes with except a nice drip tip, I would have peferred a second o-ring for the topcap for a more snug fit.
RSST produce alot of condensation but so does AGI, RSST is the way to go, great value and I will pickup a few more.