I've had rubber o rings get royally screwed by windex, but your right that you should take a quick precaution to check ingredients first.
But yeah, the Neo has been the best value for money ab I've owned. It does maybe 75% of what the top end ab's will do, and honestly 100% of what beginners can do with an ab. There are some selling for less than $50 USD on ebay.
You can get the extra doodads, but you don't need to buy branded ones. PSI for me has been anywhere from 10 to 50psi depending on what I'm doing. I'm almost always working 15mm scale models though, and larger scales have their own requirements.
Paint wise it depends on what your painting. If its tanks then take a look at AK interactive and Ammo from Mig. Both ranges have color matching sets containing various shades of yohr standard olive drabs, russian greens and so on. This means you don't need to custom mix for shading or highlighting, so much less stress for you. If fantasy or sci fi, vallejo model air and game air are where you want to be. All these paints are much thinner than vallejo model colour or citadel, so you need to thin less. I use the thinner from the manufacturer of whichever paint I'm using. I know you can just use a mix of winder and water, but I've had some absolute disasters with these mixes. Also don't assume tamiya thinner will work with other paints, tamiya paints are lacquers, not acrylics.
I clean with isopropyl/distilled water mix, but also have branded ab cleaner to back that up. I've used vallejo and ak primers. Vallejo for some reason feels better, but both kind of suck in terms of getting a solid coat quickly. Unless you're dealing with uber detailed models, I usually just use citadel primer. I actually use a lot of autoprimer as well because many resins out there suck at taking acrylic primer, but also because you want a solid coat as wargaming models are handled a lot.
Get some iwata ab lube as well, I found doing a basic disassembly on the neo, and lubricating the trigger, air valve and needle made a difference. And I bought two of them, tried one out of the box and did a service on the other before use. Big difference!
