Pretty much what Eric said, my favorite plug rod is the old school Fenwick fiberglass FS83C, of which I have 3, but I also run a Lami Classic glass and it catches the same amount of fish and lets the bugs dance, with a touch more backbone. I have heard that Seeker has replicated the Fenwick Glass blanks in the old actions, you might want to check that out if you are going custom.
That said, I have buds that run Loomis, Lami, etc in graphite for there plug rods, and they catch fish just as well, so it really is personal preference. There is just something nostalgic about catching them on old glass, especially for those of us that grew up catching our first fish on them.