This article is from the Apple II Csa2 FAQ, by Jeff Hurlburt with numerous contributions by others.
QIC-80 is a format, not a brand or a specifier of capacity. Uncompressed capacity for tapes in this format range from 60 megs (DC2120) to 250 megs (TR- 1 Extra). It was preceded by QIC-40 and has since been superseded by QIC-3010, QIC-3020, and QIC-3095 (the latter format delivers 4 gigabytes (uncompressed) on a TR-4 tape, and is available in SCSI and IDE flavors for fast operation). I'm not sure what format the 40-meg tape drive Apple used to sell used...it might've been QIC-80 with a shorter tape (they use DC2000 tapes), but it was probably different. I've never had one. For my GS, the tape drive I currently use is an Archive Viper 60S (QIC-24 format, SCSI interface, puts 60 megs on a DC600 cartridge). By: Supertimer