i was caught up in the same delema for my car... but went with the tien. there are many other bands out there that build full coil over sets that you can look into, and are a bit cheaper but Tein has the rep of being one of the best.
each tein sus system is custom made for one another and for the car it goes on. they will last the longest because they are made right the first time... the shock is mated to the spring and then both to a car.
plus if anything ever did go wrong, you dont have to buy a whole new system, they are re-buildable.
and if you havnt seen it yet... tein also offers an electronic add on for them. its a controler box for the inside of your car and then 4 boxes that attach to your struts. it allows you to adjust the dampening factor even while driving. and its wheel independed. they are also working on a automatic ride height adjustment addon.
Tein is the way to go. My quest for a set was setback because i was laid off... so who knows when i will get mine... good news is my gf is buyin me a neuspeed short shifter for x-mas... lol i love her
chris... feel free to message me if you wanna know more