Princo isn't any good. Want to see psome ictures which proof my saying ? From the 12 disc's the ussed without burn-proof only 5 succeeded. The test was done with a 16 speed plex but the disc's show up with a very strange error pattern. That you can say it isn't a compatibily issue. (The above label with Princo and the other symbols show's up as error data so it looks like a very bad production.)
About long vs short look at this link
http://www.cd-info.com/CDIC/History/Commentary/Parker/stcroix.html