I like buying parts from Summit and had bought Mopar springs from them as well, only to see Made In China next to the Chrysler Pentastar! When I put the springs on, they actually inverted a little (can you say inferior metals) and I wound up sending them back to Summit.
If you have the original springs, have them re-arched, or go with USA made after market springs from a local spring shop. More $ but worth it.
Unfortunately, this is one area Summit fails.