Mooch's Battery Charge Table shows the long life rate for Sony VTC4 at 1A and the VTC5/5A/6 all at 1.5A, he states that charging at a lower rate on those won't help much more.
Sony's listed standard rate on VTC5/5A is 2.5A with a Rapid charge rate listed at 4A for the VTC5 and 6A for the VTC5A.
While that is true, I still prefer to run at minimum charge levels. It doesn't hurt anything at all. I do this with all
batteries though, my automotive
batteries, RC packs, airsoft lipos, and it's never caused any issues. I have enough
batteries for my mods that I don't need to rush a charge cycle, and when I am home my life isn't so busy that having a battery on a charger a little while longer is going to change anything. But that is just me, I'm not telling anyone how to do their thing.