the 1150 is plenty big enough to give you room to play with and it's real sturdy...some people go with smaller cases....like the 1060....if it's your first camera the 1150 is a good choice since you can play with the placement of camera, board, power etc....you can easily fit camera, board, power supplies for both camera and board in 1150
The 380 will fit in a SE-120 case also. The SE-120 will have enough room to fit the camera, 2 battery holders and the Pix universal Pir. The new board is smaller then the old RSS boards so you should have enough room. See link below.