I own both. Crest 9200 on my tops and an MA 9000i for my beloved Th-115.
Remeber that the Crown is rated 20hz-20khz were as the Crest is rated with 1khz.
Also the Itechs, and MAi series have more power at 4ohms than at 2ohm. Consider what impedance you are going to be using them at. The 9200 is more powerful than the 5000i. The 9200 comes with a 30a plug, and should be used if you are driving it hard. The Itech/MAi only need a 20a, and can run at any voltage in the world. I like to run them on a 220v.
They are both great amps, you can't go wrong either way.
PM me if your interested in one of my ITECH 6k's.