There's nothing significantly wrong with it; but I could sell it and use that money towards a 700 - I'd like a light with 2170 in the near future. I also like to maintain a minimal collection without redundant lights...
I feel like owning a 64, 600, and 700 would render the 600 as an inbetweener that won't get much actual use. The only niche I could see it filling is a pocketable bike light for night rides - but if I'm on the trails, I won't need to pocket the light and if I'm in the city, I only need a bike light to make cars aware of me (only 50 lm or so needed). So even then, I could switch between my 64w HI and (future) 700. Yes, the Plus is perfect for both these tasks, but I don't need a $100 bike light when I have several other flashlights.
Also, going for walks in the evening, I think a little more real estate on the light would make it nicer to hold.
The Plus's tint isn't great indoors but on it's own it's not objectionable, but that slight greenish cast in comparison with my HI and H600Fc is unpleasant. I think I got lucky with my 600Fc, it's definitely a bit yellow but no green at all. Apparently. I can live with a yellow tint, not green.
The ideal SC700 for me (which I don't believe could currently exist because I don't think this LED is being produced) would be a SC700w with a XHP70 HI.