TRD Spring or Eibach
 

I m not sure which one i should get. does anyone knows which one is lower ?

https://www.scionlife.com/forums/viewtopic.php?t=50481

Eibach.

He's asking about Gen 2 judging from his avatar. Seems like TRD is 1-1.5" drop once it settles. Eibach for Gen2 is vaporware as of right now apparently. Looks like a bit of a waiting game for now. Hotchkis was also working on a kit for Gen2. Goldlines are out as well if I recall, those are supposed to be around a 2" drop. Run a quick search and you'll find a few things.

I have the TRD springs and just yesturday my buddy with stock springs and I, parked the cars next to each other. i should have taken a picture of it. But the TRD springs will lower the car about 1-1.5 inches. More so in the rear. If you look at stock the rear sits a little higher, the TRD springs level out the car more. Overall the car looks way better. It doesn't looked dumped, but it does look more aggresive. And the handling is much better.

The dealer is installing my springs before I even take delivery (allegedly)...the TRD springs that is. A quick question, remembering I am a noob at lowering cars (this is my first)... Are they going to or do I need to have an alignment done after? Also, is the camber a concern? Thanks for any help.

The installation instructions for the TRD springs calls for an alignment.
I waited about a week after I installed my springs to allow them to settle. When they did the alignment there was no change to the rear. They did toe in and camber adjustments on the front.
My car has a slight negative camber on the rear. I think that is by design. Clearly it was checked and met the specs on the alignment. Many cars have that now. It was very noticeable on my completely stock Mazda3. I know Randode said his had negative camber on the rear as well.

I went with the TRD lowering springs, and im pretty satisfied about the whole drop that i got. ( i knew it wasnt going to me much) But i live here in idaho there is snow here half the year. and another thing i didnt want to wait for other springs to be released.