The C1100.4 is a good amp for the money,
If you want something that's going to give you 150x4 your going to pay 600 to 1200..
It's an audible upgrade but unless your running highend comps and have extensive dampening along with ideal install techniques it's not worth it for the average person..
The SS 4.920 is a a tad better..
Othe options are zed zapco,arc, soundstream human reign, lunar
Helix