Look, I like guys. I like it when guys appreciate my appearance. They have to look at me to do so. I'm not even offended when they mutter an "mmm hmm" or whatever.
The offensive part comes when someone, no matter gender or sexuality, express their appreciation (or attempt to demonstrate power over me) in an manner that hijacks my attention or disrupts my activities.
They do this by:
1. stopping at the end of an aisle, looking you up and down, and staring at $BODY_PART for several seconds.
2. Initiating small-talk from a non-interpersonal distance and being persistent about it if you don't respond (there's a difference in expression and tone vs. being neighborly or whatever). There's a difference between "hi!" or "excuse me" as you move past and "dang girl, how you doing?"
3. Making comments and then following you around (sometimes continuing to comment unless you stop and say _something_ to sooth their ego).
re: How many gay: I have yet to have a gay guy hit on me, or check me out. Some do judge my outfits. I have a reply elsewhere on the difference between normal perception, judging clothing, and "male gaze" (which TBH should be called "aggressive sexualized gaze" for precision and to avoid discussions like this, even though the shorter form is precise enough.
re: How many male: I dunno, the masc-presenting trans people I know are too self-conscious about appearing creepy to engage in these behaviors. So are most of the techies I run into :) The straight trans-masc guys I know are also tend to fit in the "def dudes that appreciate but aren't creepy about it" category.