On a standard 6 hour T-120 tape this is how it works:
SP mode - 2 hours (Best quality, I recommend it)
EP/SLP mode - 6 hours (Not as good but, works if need-be)
EP and SLP are the same thing.
On a standard 8 hour T-160 tape this is how it works:
SP mode - 2 hours and 40 minutes
EP mode - 8 hours
On a standard 9 hour T-180 tape this is how it works:
SP mode - 3 hours
EP mode - 9 hours
On a standard 10 hour T-200 tape this is how it works:
SP mode - 3 hours and 30 minutes
EP mode - 10 hours