Secondary Glass Carboy

I got a couple questions about a glass carboy.
(#1) Does a secondary fermentation glass carboy make a difference?
(#2) How long should you wait to transfer beer from a plastic fermenter into a secondary glass carboy?

1. nope, same as a bucket or better bottle, just made of glas instead.

2. Some don't use a secondary at all except for really long aging brews, like RIS or Barleywine. But if u are going to use one, any time the gravity is stable, ie the same for three days, u can transfer.

I gave up secondary fermentation (except in the cases mentioned above by "Pratzle") about two years into homebrewing. I've been just doing 3-4 week primaries and then right to bottle except when I need to bulk age a great big barleywine or something, or dry hop. I can taste no difference in quality in my regular beers. Since I've got two glass carboys and two Better Bottles, the glass carboys pretty much just sit gathering dust.