I normally use a Klon for low gain into a Varidrive or FD2 for higher gain.

*I play an old SG with single p90 or Les Paul with HB through a Tophat Club Deluxe*

Well it is here and it is awesome! I find it prefers my darker soounding guitars as it is a bit bright. Nothing the tone control cannot handle though.
Two channels of overdrive with a ton of headroom for boosting (TONS of headroom). This thing will replace my FD2 once and for all and has more definition to boot.
That said, my Klon is still numero uno and two Klons are pretty freaking awesome too!