On my 2005 Tacoma the rear leafs were shot. They were sitting on the overload leaf when the truck was empty and bottomed out frequently. I did not get the TSB under warranty.
After looking around at my options I liked NWOR's springs the best. I got the springs that are supposed to add about 3/4" lift and 700 lbs of load capacity. With new U-bolts, shipping and sales tax it was just under $700. The people I talked to there were helpful and knowledgable.
With an extra pair of hands install was easy and took 2-3 hours. The U-bolts were a little wider, but they didn't take much effort to muscle in. All and all, everything fit up nicely. I could have re-used the old U-bolts but there would be little to no thread protusion. When first installed they added 5" of lift! After jumping on the tailgate a bit and some driving it leveled off to about 3" of lift. My old springs were shot so I'm guessing I was 1-2" below stock to start, so 3" is about as advertised. The rake looks fine.
I've only put about 50 miles on them so far, but the ride is great. Slightly softer then the stock front (some bumps I only feel once) with about 100 pounds in the back and a cap. True test will come this weekend when I hook up the trailer.
The springs have a grease fitting but I'm runing them dry right now as I don't have the right fitting. I'll take care of that tonight.
All and all i am very pleased. A very good option if your springs are shot and the TSB is not an option. (note: Toyota quoted me $1800 to put in the TSB springs and a local shop wanted $600 to re-arch and add a leaf)
Also, once the old springs were off it was very easy to see how bad they were. The first and second spring were seperated. The overload leaf (the thick straight one on the bottom) had negative arch of almost and inch. I wonder how close they were to breaking!