External HD VS Flash Drive Sound Quality Question

Hi have an Oppo BDP-95. I am up to around 25 Flash drives which is getting ridiculous.

2 questions (hoping for folks who know the definitive answers; I have my own guesses, bu that's all they are.)

1. HD Tracks has written that the Flash drives sound better than any spinning disc or drive due to lack of jitter from lack of a spinning disc. Is that accurate?

2. I have noticed a new generation of external hd's that get all there power through the USB port, & do not require an out board power supply.

A. Would there be any detectable sonic difference either way? If so, which is better: the cheap wall wort power supplies or getting power solely through the USB line?

B. The Western Digital USB drives with no power supply have a proprietary cable that looks quite cheap. Would the lack of an audiophile USB cable be sonically problematic?

I'm basically trying to decide whether to ditch the lash drives or a USB hard drive; & if so whether to go with a powered or unpowered drive. A couple +'s re the new WD's: they are teeny & they run cooler than the Seagates I've used.