The new polymer notes shouldn't smell musty, but there are already people out their trying to forge them!
"Here in Scotland" pretty well all the ATMs will dispense Scottish notes, and as we have 3 different banks (Clydesdale, Royal Bank of Scotland and Bank of Scotland) all producing different designs of note, I suppose it's no wonder some English retailers get confused and refuse them. We nearly had to go hungry once, after driving all the way from Edinburgh to Sidmouth - 450 miles - then have the chippie refuse our Scottish £10 note (back when you could get 2 fish suppers for under £10). All wrapped up and ready to take away, when they said "We can't accept THAT". Fortunately for our rumbling tums, my husband found one English £10 note in the car!
Some folk have made a big song and dance about it, protesting that Scottish notes are "legal tender": in fact they are not, although they are "legal currency" - subtle difference - look it up! But it's at the retailer's discretion whether to accept or not. So now we spend all out Scottish £££s before crossing the Border, then pick up some English notes at the first free cash machine on the other side (those in motorway services are usually NOT free!)