I try to give praise where it's due, and I try to give it with enthusiasm and sincerity. I prefer, as they say, to accentuate the positive -- to celebrate it, even.
Likewise, I try to be careful with absolutes or grand proclamations; I may do it for obviously hyperbolic purposes, when everyone knows I'm just being enthusiastic and care-free, sure. Yet I don't want to come back and embarrass myself later (not anymore, anyway). Therefore I give a lot of props but I do what I can to weigh them before I give 'em.
With that established --
The Risus Companion is among the best game supplements I have ever purchased, and its GMing advice is possibly the best I've ever read.
I don't care if you play Risus or not; you'd do well to read the Companion yourself. The "Dirty Little Thrills" section alone is worth the price of admission, and even outside of it, everything in the book is useful, somehow, whether you play Risus or not.
And even if you never do, the book will make you laugh, and that's never wasted money.
To every voice that told me the book was worth every penny, I add my own.