I too used the Deep Crystal system for years...it is a very good system....there is always a newer, better system...I have since moved on from DC however it was my introduction to the higher level of detailing that many of us on DC aspire too...if you have it by all means use it...the basics are there...clean..polish...then protect. You will get a nicer result than you would with almost any single product because you are prepping the paint before you protect it...as you will read often on here the more you do to prepare your finish the better the final result.