These sisters share the same lineage, which is Biscotti x Sherb Bx1 x Jealousy F2. It's unclear if Permanent Marker S1 is a phenotype of Purple Octane S1, or if the two had different Jealousy F2 pollen donors. One thing that's clear is they are both amazing expressions of the same genetics; clearly marking how important the selection process is.
Purple Octane has more of a grape profile along with the peppery fuel forward flavors. Whereas Permanent Marker has more floral funk and soapy essence along with the sweet fruity (grape) flavors.
While each strain is versatile in that they can be enjoyed anytime of the day, Purple Octane can be a better choice around bedtime, since it can induce more sleepiness after the initial creative and euphoric effects fade away.
Both Purple Octane and Permanent Marker will make you look like a pro in your grow, even if you're new to the hobby. The harvest results in some of the loudest flower you'll encounter, with premium bag appeal and flavors you wont soon forget!