someone just wrote that the PAPIs were for instrument flying...wow...I'm shaking my head on that one.
Then you shouldn't be.
It's most unprofessional to drag a light single in at 3 degrees, power against drag, especially if there's a built up area underneath, unless you are going for an ultra short landing at a strip with no obstacles.
'The lights' are for instrument traffic to translate from ILS to visual for the landing, so they reflect the 3 degree glideslope of the ILS. They are not appropriate for light singles.