when the private key is spent, use a wallet that has coin control to select the desired inputs, ignoring dust.
dust is not an issue that people make it out to be
Exactly.
IMO....A coin must be loaded with exactly the face value...and also match the year issued...
example... Casascius 1 btc 2011 error should be loaded with exactly 1 btc in 2011...and not in 2012 or any other year for that matter
What about the 1Sochi and 1Enjoy dust on a bunch of Cas coins? I've heard others say they are more valuable with that dusting, as it's from the USSR World Olympics.
Here's a look back at our old legendary pal Zepher's poll on this very subject.
https://bitcointalk.org/index.php?topic=1546441.0He's been gone over 2 years now; RIP, yet still a f*ckin legend!

Others can say....never heard of this and never seen a casascius coin selling with an extra premium just because they were dusted with anything or from anyone. I couldn't care less if Satoshi himself dusted it.
Our physicals are unique in the collectable world. Not only do some people want the physical purity, but also the bitcoin loading purity. Count me in for the latter.