will there be accessories etc?
do you trust the person you are trading with?
what condition is the glock in?
these things i suspect would control whether people would say it is a good deal.
ultimately, you are the arbiter of whether it is a good deal.
if you already have enough black rifles and no handguns, then perhaps a glock would be a good addition to your collection.
"...and which is worst of all, continual fear and danger of violent death, and the life of man, solitary, poor, nasty, brutish, and short."-Thomas Hobbes, Leviathan
...What he meant to add was, "unless, of course, all responsible citizens are armed to the teeth."