I've used both. Purple Power seemed to cut through grease and grime a bit better. My go-to favorite is POR-15's Cleaner/Degreaser. Really cuts through the gunk and doesn't leave a film once rinsed off.
My go-to degreasing routine is to grab a couple cans of Gunk Engine Degreaser and go to town. It does an okay job and is cheap but it leaves a residue once hosed off. Then I go with POR-15's Cleaner/Degreaser and its like brand new when I'm done.
Cleaner Degreaser
Remove oil, dirt, grease, & more with POR-15 Cleaner Degreaser. This paint-safe, non-solvent cleaner works in just one application without leaving residue.
por15.com
My go-to degreasing routine is to grab a couple cans of Gunk Engine Degreaser and go to town. It does an okay job and is cheap but it leaves a residue once hosed off. Then I go with POR-15's Cleaner/Degreaser and its like brand new when I'm done.