To me the new Tundras sit level as is. The truck sits lower than any other full-size truck on the market today, front and rear. It's certainly easier to get in and out of compared to others.
To me one of the best features about the Tundra is that it's low-to-the-ground, even the 4x4s, than every other brand on the market.
In fact, a bud of mine was looking at my Tundra yesterday and he said "Is that thing four wheel drive?" When I told him it was he asked if I had it lowered. He also said that even without anything in it that it looked like it was fully loaded.
From what I have researched, I think the Readylift or the Daystar are the way to go.
My reasoning..... It is a solid piece that mounts between the strut and the "A" arm.
I had a leveling kit on my Titan and found that a lot of people that had the spacer that goes between the coil and the strut didnt like it. When they went over a minor bump, it sounded like the shock was overextending and bottoming out on itself. My buddys dad oped for the this style and very soon after bought the solid top mount type from PRG Products.
Actually for the Titan, I wouldnt buy the Daystar because it mounts this way. The Daystar for the 07 tundra apears to mount on top of the strut and not IN the strut. I dont know how big I am on the bolt extenders however. They seem pretty cheesy.
Just my $0.02.........