Rejex was developed for jet engine turbine blade protection. It protects the blades from pitting due to jet fuel.
It's a very reflective sealant to begin with. If you like a very bright, plastic look, then Rejex is your answer.
Your problems with Zaino is simple over application. The answer would be to use the Z-AIO for cleaning then Z-CS and walk away. Couldn't be any easier than that!
Other sealants? Sure, there's Optimum, Klasse, Meguiars, Poorboys etc. It all depends on the look you're after and how much time or effort you want to spend for best results.
Klasse is pretty much the same as it has been. One is the AIO, the other, the sealant. The sealant can be a PITA if over-applied as well.
I've not use Optimum, but hear good things with that sealant.
I wouldn't sweat it. The easiest in my book is the Z-AIO and Z-CS application since once you apply CS, you just walk away, no buffing off. Simple right?
I do believe there are a few sealants that may offer then same (wipe on, walk away) but I'm not sure which ones offer that. Most you still have to buff off.
As for Rejex, it's a big thing on Porsche forums, but I now just use it for wheels now since I hated the look of it. Protects very well (it should due to it's original intention) and do not have issues removing it.
Regards,
Deanski