This takes into account talents etc. but watch out for the 'nil' return. You will get a 'nil' if: 1. * The spell cannot be cast on the unit. i.e. attempting to check range using 'Frostbolt' on a party member will always return 'nil', similarly testing 'Heal' against an enemy target will also return nil. 2. * If the unit is not 'visible' (see API UnitIsVisible) then you will get a nil, and not a '0' as you might expect. 3. * The unit doesnt exist (e.g. 'target' when you have nothing targetted) 4. * The current player does not know this spell (so you cannot use 'Heal' to test 40 yard range for anyone other than a priest)