I have the SC600w IV HI, the SC600w IV Plus, and the SC64w HI. All great lights, but serve very different purposes. Think carefully about how you intend to use the light, and then buy the appropriate one.
My SC600w HI is the best all-around outdoor light. Good throw (for such a small light), but still usable spill. No "tunnel effect" due to the spill, but the spill is dim enough it doesn't blow out your night vision. You can see far with this light.
The SC600w Plus I use for a bike light. Bright, efficient, and a decent wide beam. Not much good for throw, but on a bike the wide bright spill is more important. It might actually have good throw on paper, but due to the bright spill it blows out your night vision so you can't see far.
The SC64w HI makes a great EDC. Very small for an 18650 light. Great beam and tint. Not as throwy as the SC600w HI, but still has enough throw to make it a decent light for outdoors too. Downside is that it can't maintain max for long, due to it's small size.