montague
I sold my HP-CS to Doogsatx for a 105 and the upgrade was measurable. No more spitting, better atomization and easy cleaning. Badger hands down is better.
Usual disclaimer about airbrushes being subjective, blah blah...
Back in 2011 I got a 105 and a Renegade (pre-Krome). Disliked them both and sold them. Thing I didn't like about the 105 was the double-tapered needle, since it's quick to go from no paint to way too much paint. With the Renegade, the balance felt funky, the cup looked like someone just stuck a grinder in there, and the trigger action felt very rough and clunky. That and Badger needles are very exposed.
My current airbrush lineup is as follows:
Iwata HP-CS (x2) - A good, solid workhorse brush. I like the balance and and the spray performance. Something about the cup design makes cleaning it more of a pain than other brushes.
Iwata HP-C+ - So far this is the best airbrush I've ever used. Awesome control, good balance, fantastic atomization...a very real upgrade from the HP-CS.
Grex Genesis XN - I had a Tritium briefly. Loved the airbrush but hated the trigger action so I sold it. Finally picked up just a basic Grex...this one's for fine work, has a .2mm needle and a smallish paint cup. I've used it on a few projects and love it. It's not as precise as the HP-C+, and the trigger's a bit looser than Iwatas in general, but it sprays very well and is super-easy to clean. In fact, I haven't had a single issue with needle stick or anything like that yet.
Harder & Steenbeck Evolution - Good airbrush, but it has a tendency to spit when you first depress the trigger (none of my Iwatas do this and it's really frustrating if you're trying to do something like mottling). It also sprays bigger than it's needle size. The .4mm pattern is wider than that of my 0.5mm-equipped HP-CS. Getting ready to sell it.
Harder & Steenbeck Infinity - See Evolution above.
Iwata Custom Micron CM-B - No way I'd pay the usual price for one of these beauties, but I scored one for an amazing deal on eBay. I've only sprayed thinner through it so far, but wow. I could literally use it as a pen.
Olympos HP-100A - Olympos airbrushes are what's now Iwata's High Perfomance + and Custom Micron lines. Some say they're even higher quality than the Iwata pieces, and since they aren't as well known they can sometimes be had for a steal on eBay. Case in point, I got this one - the equivalent of an Iwata HP-A+ ($190) - for a whopping $33.