Assuming small parts is all you're working on, and assuming you want a pro quality tool, then........
For $700+ go with a Sata Minijet. If you always have to have top of the line, then it will make you happy.
For a little under $250, I'd go with an Iwata LPH80.
I'd equip either one with a PPS equivalent or copy.

If you're looking for an inexpensive full size gun that can atomize thick materials (without cranking the pressure up....any gun can atomize at high pressure, but it wastes material), lays a nice finish and costs next to nothing, My pick is the pntgreen LS230.
same regulator and pps recommendations. For a cheap workhorse, I graduated from the HF purple to this and am not going back.
Link

The LS230 is my current workhorse for smaller parts + I did all the primer and basecoat on the GTX with it + some of the small parts and areas am also using it for clear.
My kit included a 1.8 + 1.4 tip but only the 1.4 is available now which kind of sucks.
I liked it so much I bought 3 of them but the first one is still working great.
Only drawback is the fluid needle adjuster threads are coarse, so a little turn makes a big difference.

My GOOD gun is an Iwata LPH400. ATM I only use it for clear. About $500 at summit or $450 with a discount code.
This would work really good for you but is total overkill for some valve covers.
The Devibiss stuff I've used is also total overkill though it works well.

I have a tiny Devibiss starting line touch up gun also. I have used it a few times for small parts/areas and get a pretty nice finish with it.
Most pros would not go anywhere near the starting line, or the amazon gun....and if I were a pro, neither would I.
It's just a 1.0 tip and I run it close to wide open and usually mid-20s for pressure.
It feels terrible to use because the spring in the trigger is about 2X as stiff as it needs to be and it has a notchy feel.
So, pretty clunky. Works fine for how little I need it.