I know two owners of these, codemonkey (Lee) has the 120, and I have the 100. The 150 and 100 are excellent in my experience, I don't believe they give away anything to their competitors. If I ever have that sort of money, I'll not hesitate in supplementing my 100 with the 150.
Just be aware the 150 is f/7 and is therefore not exactly a small scope...and at 1050mm focal length, you're not really giving up much focal length. I'd put money on you getting better results out of the box with the refractor