I went through a similar predicament when deciding to jar several tins of my favourite Peterson's Signature flake many years ago.
After much trial and error I've found that storing the flakes whole produces a far more consistent flavour over time. With less area open to fermentation/oxidation the flakes mellow but lose no flavour. I just rub out what I need at the time and seal up the jar.
Jars that contained rubbed out SF show a significant darkening of the ribbons and for me a marked change in their flavour profile, it tasted 'watered down' and weak and also lost it's woody / caramel flavour I love so much.
Jars containing whole flakes show almost no change in appearance but the time in the jar rounded out any rough edges that were there fresh from the tins. Nowadays as soon as I open a fresh tin it goes straight in a jar to mellow and keep from drying out.
This experiment was only conducted due to several of my tins being compromised. I keep all my SF in the original tins but it was an interesting outcome.
Happy smokes.