I think that the basic point is that you shouldn't consider a single razordon as shooting threat.
Take a minimum of 2 razors. 120 pts.
The 2 razors shoot on average 15 shots. Typical shooting units of other armies, usually cost 100 pts for 10 models (10 shots).
The range is only 12", but 8" is a high move, so they threaten almost the same range of archers (archers' range with move is higher, but razordon's move is better so they're easier to move across the battlefield)
They are not so dependant from handlers... if you're using a Slann, you already have the constellation to reroll 1s for free.
on a 50% they can stand and shoot, which is a big bonus in my book, and the save 4+ is solid.
So, for 120 pts you've got 15 shots, move 8", 8 wounds with save 4+, a possible stand and shoot and nice close combat abilities. Not bad.