Zubon at Kill Ten Rats has posted his top 6 reasons he doesn't use the PTR. Reason number 2 I agreed with: I don't want to get bored of the new content when it's on Test. And I would add that getting bored with it before it hits the live servers means I'm not experiencing that content with my friends on my usual server.
But there are other reasons gamers don't play on the Test Server other than non-spoilage. Too much of hassle to patch and transfer toons? Test Server pick up groups (ugh)? Not paid to beta (go Zubon!)?
Tells us, if you avoid the PTR, why? And what would get you to change your mind?