I would recommend the STX Gladiator CP if they still make it.
Another is the Brine Eraser CP. It is a new CP and I believe it has a lot of potential.
I have also looked at a Gait Sentinel CP.
All 3 have great reviews and are some of the ones I would try.
I currently use a DeBeer Icon CP. It is about 1" thick and allows for great mobility.
Check out
LaxShopper.com - the Lacrosse Marketplace for reviews on the said chest pads.