I have a set of MSP springs on my P5, purchased them from one of the forum members here. At first, I didn't like the way they sat on the car, meaning, the rear had dropped about 1" 1/4, while the front only dropped 1/4 of an inch. Yes, 1/4 of an inch.
So I was very disappointed and fustrated with the new look of my P5. I went to Autozone to buy some "lowering clamps" (I know, they suck - I'm totally against it) but I was so desperate to see my car leveled that I didn't care.
To make a long story short, the clamps didn't work and I end up cutting one coil of the front ones (I know, getto, But...) I've told people not to cut their springs, but after I did mines I would recommend to do it, but only in this application. I'm not sure this will work the same on every set of springs... They car handles SO much better, and it does NOT bounce at all. It rides just like before, but an even look. I'm really happy with my MSP springs
I'm not sure if the MP3 springs are the same as the MSPs, but if they are and you don't mind cutting the front one, I highly recommend you to get those from eBay. I paid $100 for mines shipped to my door!
This is what they look like: