I like trading with people in person. In person, if I like somebody, I am interested in hearing their sounds as an extension of their personality, even if it is a minimal presentation. In person, it's basically like trading business cards if we're not talking about pro stuff.
I am much more sympathetic to international trades. In that case, even if it's not my style, it's still like a sociological study.
Shipping prices in the USA just went up, so considering that I do pro CDRs, but I've worked for a long time on this stuff (6 years in both cases of disc releases, would be nice to afford bulk CDs), it would have to be a very special case that I would trade 2xproCDR for 1 CD internationally, especially if I am sending a jewel case, and I'm getting a pro CD in a slim little cardboard sleeve. And getting a xerox insert in a plastic sleeve with a spray painted CDR that has 10 minutes of sound on it, that seems engineered for trying to rip off people in trades. I think more people should outrightly specify "pro CDR" rather than simply "CDR", because there is a distinct difference, and it costs about the same per unit as a CD if not more, only lacking the initial bulk investment, and I think pro CDRs look like they will last longer than consumer blank CDRs, for the 5% of people who aren't putting everything on their hard drive immediately anyway.
I also have a radio show, so I like having new stuff to consider for airplay. It's an added motivation to trade.