I know there has been some mixed opinions about Airlift 1000 HD air bags on this forum.
A little background. I have a 2018 Ram 1500 4x4 Big Horn. Rams ride darn near like a car however, I believe one reason for that is Rams have coil springs on the rear vs. leaf springs. So with that comfort comes a little trade off of “firmness” when towing. I have a e2 Equalizer trunion WDH professionally installed and while towing my 2015 2295 I still felt the rear suspension was a little soft and had some side to side movement not in the trailer swaying but just the truck rear end. Nothing dangerous by any means. I would feel semis passing before they were along side me. I looked at Sumo springs and read reviews and decided against them. I have a friend whose business is delivering TT’s to dealers from Elkhart and he recommended air bags. I thought it was more involved than I wanted to get but after talking with him and researching, it was the route I decided to go.
After looking at the various options i.e. Firestone, Airlift, axle mount vs. spring insert, I decided to go with the Airlift 1000 HD vs. the 1000 spring insert based on weight capacity. I know the bags don’t increase the truck weight capacity but having the extra capacity helps due to downward forces and simple physics when going over bumps and dips. Airlift comes with a lifetime warranty against defects. Another plus is that when not towing you decrease the air pressure to 5 psi and you regain all of the comfort of the original suspension design.
After pricing having a shop install them I decided to do it myself as I was capable and don’t get my hands dirty nearly enough lately. One thing I didn’t like about any of the kits were the air hose fittings. They were barbed and clamp fittings and the tee was plastic! Really??! 
I purchased brass PTC fittings for all connections (Air filler valve, Tee, and air bag connection fittings) from a couple different sources including etrailer, King Bezos, and Firestone Industrial Products. I also purchased a tubing cutter to ensure a nice clean 90 degree cut.
The hardest part of the installation was rolling and folding the air bags enough and zip tying them in order to slide them between the coils. Airlift recommends a spoon shaped tire Iron to assist with sliding the bags through the springs but since I didn’t own one, I absconded one of my wife’s wooden cooking spoons. I can assure you she didn’t want it back when I got done with it. 
One of the many tips and tricks I learned from YouTube is to spray the coils with soapy water prior to sliding the bags through the springs to provide some lubricity which helped immensely. Once you get past that part of the installation the rest was easy. Another required step (at least on my Ram) was removing the wheel well liners in order to gain access to the top of the coil spring where the air hose connects to the air bag fill fitting.
Once the bags were in, I ran the air lines along the frame back to the bumper using plenty of zip ties to prevent movement and contacting any hot exhaust surface. I’ve read complaints about having to replace air hoses and fittings due to leaks. I imagine those leaks were caused by abrasion or heat. I covered all my hoses with wire loom rated for high temperatures (no brainer to me). I’d be surprised if any shops take that extra effort to install loom over the hoses.
I did not install an onboard compressor and have only one filler valve next to my license plate that controls both bags since I don’t have an uneven load. For my towing purposes, an on board compressor was not worth the cost or trouble of installation.
So after a few hours on a Saturday, they were installed. I pressured up the system and leak checked everything with soapy water and everything checked out.
So now came the decision on inflation pressure and field test towing my 2295. After watching a couple of reviews I decided to inflate to 40 psi (max capacity is 50 psi) The air bag does not fill the entire vertical travel distance of the coil spring so when I hitched up the trailer the spring did compress but once the spring compressed against the air bag the rear end did not go any lower. I see lots of photos of rigs and despite having a WDH I still see some sag. When I hitched up there was not even the slightest dip below perfectly level. I stopped at a gas station and was talking to another RVer and he commented on how level my rig looked. Ahhhh validation 
We towed just shy of 1,000 miles round trip and I am extremely pleased with the results. The springs stiffened up the rear end just enough to eliminate the side to side movement in the rear end without make the ride rough like Sumo springs tend to do, so I’ve read. To be honest the bags did not increase the “roughness” one bit. Although I could see the semi approaching in my mirrors, I never felt it passing as I had previously experienced before installing the air bags.
Updated: Link to PTC to schrader fittings for air bags. PTC air valve filler fitting purchased on Amazon. Cust and paste description below.
https://rideriteserviceparts.c...-ptc-straigt-fiting/
VIAIR 11490 DOT Inflation Valve (for 1/4" Air Line) (DOT Approved, PTC Style, Nickel Plated) (Pack of 2)
Great modification IMHO
Cheers,
Jonathan