I have the original Donahoe Racing coilovers (now ICON). I think the Valving cannot get any better, Tried stock.. sucked, Bilstein 5100s... Sucks
Mine DR shocks have lasted over 2 1/2 yrs of hard driving (jumping railroad tracks, curbs, sidwalks,
) and abusive offroading (Mud, clay mud with lots of iron in it, no rusting on the cans or shaft, no pitting either.) around 45 - 60mph tops with no jarring/aggressive rebounding of the shock throughout the suspension or the throughout the steering wheel thus losing straight forward tracking of the front wheels in 2wd at a setting of 2.5" of exposed threads. This was all done on washed out roads with 6" - 10" holes. I tried the 3" setting, it became too rough a ride for me even with the ARB bumper and winch combo. 2.5" is perfect on the Extended Length Donahoe Shock. I feel you don't get the lift like you'll get on the Camburg coilovers but you will have an even 5" uptravel / 5" wheel downtravel at that setting. I have measured mine and thats what you get. 10" is The maximum amount of wheel travel you can possibly achieve with the stock IFS setup using the Donahoe Extended Length Coilover using Aftermarket Total Chaos or Camburg Uniball A-Arms allowing for the extra droop travel and upward extension of the Upper Control Arm without any binding like the Stock Ball-Joint Upper A-Arm encounters. Plus you won't have to use straps like the Camburg Coilovers making sure they don't over extend putting tension on the spindle. The ICON shocks have internal limiting straps to avoid this. Mine have 1/2" of room between where the uniball and spindle connect to the spindle and still yield 10" of wheel travel not putting any unessecary tension on suspension parts like tierods/steering rack, spindle, lower balljoint, etc. This is all why I chose the coilovers I have.
I would have to say the Camburg valved coilover for the Tundra ( Sway-A-WAy/Racerunner shock) will gain more lift if thats what you're looking for in the 2.5" body shock but you will lose your down travel.. It takes 5" ( 6" fully due to low tire pressure and the heavy front end using 33's) of jacking the truck the truck up before the wheel even starts to lift off the ground. People with SAW coilovers on SoCal Tundras.Com said they had almost zero down (also called droop travel by some) and you can verify this with Camburg if you're going to start cranking down on that collar to compress the coil spring gaining extra lift.
I've just sent my coilovers in for a rebuild and will be able to share how they've held up (Seals, nitrogen still in them, etc.) by next week for 2 1/2 yrs of hard use. They were already IMO perfect, but I just wanted to get them rebuilt to make them last for years and years to come. Plus I am getting an upgraded/updated coil spring ( Released March 08' ) because of all the weight up front and to see "If" the Springs sagged at all. I've got lots of steel up front so I'm wanting to see if the 650 lb spring rate is enough. There's 3 skidrow skidplates, ARB bumper (heavy) and a winch, plus I will be adding sliders next for even more weight.
Thats my take on the DR shocks and what I know about the Camburg Shocks. Check out
SoCalTundras for more discussion/topics and facts about the two coilovers from those who have put them to the test in the desert/jumping.