For a 150g i think you would be fine with the XP 3000 or SWC230 Cone. The build quality will be similar and performance would be good on either or. The differences is the xp 3000 uses a bubble blaster pump and the swc230 cone uses an askoll. The 230 cone will break down completely meaning everything comes apart from the body. The XP will need to be in 5-6" water and the 230 will need to be in 7-10" water level. Just choose whichever makes you happy : )
As far as SWC and Coralvue goes all kinds of rumors i see in this thread. To make it simple, they use to both be made in the same china factory. Now they are made in different china factories. We'll just leave it at that.