it's good for certain copy protections, since it allows to copy only the first session, which is needed for some copy protections. clonecd supports that too, though. besides, plextools sometimes crash on my system. basically, if you got a good cd ripper, clonecd, blindwrite, then you don't need plextools, because clonecd and other tools will do everything faster and better.
there's also a cdtext player included, but you can get it also as a separate programme from the plextor site. the cdtext player, which is part of the plextools is, however, a little better, than a stand alone version of the player, because it allows to play audio cds from any drive, not just from the plex drive.
in any case, the plextor cdtext player is uncomfortable. I found another one, which is freeware and more comfortable. so you see, the plextools is a good programme, but there are better alternatives