I also only have used stamps when I was starting since I got stamps from friends. Just very later that I was able to have some mint stamps.
Well, I collect both of them. However, I prefer used stamps, as some of them are very rare and hard to obtain these days. But they could also be in a bad condition if you buy them online, and that's why I won't generally buy stamps from the internet. A nice advantage when buying / collecting unused stamps is that the details are clearer and, of course, there's some kind of joy when getting something fresh. But most of my stamps are used ones.
Agree that those who would want rare stamps, be more into used stamps cause canceled stamps are rarer this days.
