Vintage Krell Amp... Which would you choose?

I am in the market for a new amp, and I was thinking instead of purchasing something new, why not purchase a preowned amp. I always admired the krell sound, but it was just way to expensive. I would like to know if there was "ONE" krell amp either class A or SS that you can go back in time and purchase, which one would it be? It will be paired with Martin Logan's.

Thanks,