I am always impressed that honemeisters "test shave" after honing a razor. I often wonder if these guys have any arm or leg hair left on their bodies, and if their cheeks are insured against loss, damage, scaring, or (gasp) hair-loss!
Anyhow, when I'm wondering if my razors are sharp, I don't go for the cheek whiskers. Instead, I have two areas that stubbornly refuse to yield to my straight razor, though the DE gets them nicely.
First, the half-inch or so directly under my lower lip--you know, the whiskers your tongue feels if you lick below your lower lip. For some reason, only my most wicked-sharp straights will get those. They are dense, coarse, and in a sensitive spot.
Second, the hollows on my lower neck on either side, spaces about the size of a half-dollar, where the whiskers also grow in several directions. I used to think this was due to the whiskers hiding, but the DE and even the disposables get them. With the straight, I've had trouble and, again, it's the really sharpest razor that gets these hairs.
So...what are your "test whiskers"--the parts of your face that tell you immediately, assuming your technique is good, that your razor will do the job?