I am very particular about my paint. I have always taken my wife's and my cars to a higher-end TOUCH car wash. Why? I have a vendor who manufactures the "brush" material that is used in the touch car washes, and I know it's capabilities. Some of them are a foam based brush, and some are a polyester-based brush... but neither will harm your car. It is designed to be softer than the paint, so it will not/can not harm the paint. Someone made a comment above about it picking up dirt from other cars, and there is some truth to that, but in the higher end car washes they are designed to rinse that off of the brush material between each washing, unlike the gas station ones. Your run-of-the-mill gas station car wash has the soft brush material, but that's about where it ends. I avoid them, but would not be opposed to hitting a cleaner one that is higher end in a pinch.
The touchless car washes are worthless. They will leave a dirt film on the vehicle, which will ultimately harm the paint, and with the high pressure water, I have seen and first hand where it has peeled some paint off vehicles. For those that say they wipe the car afterwards, that's even more detrimental to the paint. That's what creates swirls and microscratches. If you notice most gas stations that have them are replacing them with soft touch washes. Touchless may have been a better option in the early 90's when they came out, but they've been surpassed by the current generation of touch washes because of the non-scratch brush material used today.
Hand washing can be OK, but you also have to be careful about that. It can be much more damaging than a touch wash. Swirling comes primarily from hand washing done incorrectly, as a touch car wash cannot "swirl" since those brushes are typically applied in a straight fashion.
Nothing can help a car more than frequent wax jobs (with a high quality wax). Not only does the wax keep the cars pretty, it also creates a protective coating that repels dirt and protects the paint. The car will stay cleaner longer, and when washed, will come cleaner easier. I also wax my windows, but that's a personal preference. I use
Collinite #845 insulator wax, which came recommended to me from an aircraft owner's group that I'm part of. The guy that swore by it was part of a sea captain's group, and they use it to wax the hulls of the yachts and such. I've used this stuff on my plane and my cars. It's better than any "car" wax on the market. It's solid at room temperature, and you need to shake the heck out of it to liquify it, but once it's thinned out, the stuff is marvelous and lasts a long time. Less is more on the insulator wax... so thin you hardly see it, and then wipe it off. I'll use about 1/4" of the bottle to do the entire car. It works even better when you do a second coat a month later.
Here's a pic of my car freshly done:
