I've had no luck at all with PTFE in a lot of projects.
The marine blue grease is good but messy and will stay messy for a long time.
Sometimes I have luck with white lithium grease.
In a pinch I will use some of my zipper lubricant
It is OK for a lot of sliding applications.
The real question is if you need lubricant or are really trying to prevent corrosion. Some of the 'plastic' slides are somewhat self lubricating. If your concern is corrosion, an inhibitor would be better. I use Boeshield T9 sparingly. I would keep the T9 off of the actual plastic slide material, just on the metal parts.