Supreme and Pran are good, if you can get them.
Natco do the best whole Coriander seeds I've come across and their whole Cumin is very good.
I agree with the best advice and to buy only small 100g packets in both ground and whole spices.
Once opened, Ground 3months, Whole 12months.
The ground Paprika seems to have no shelf life at all, so I would check that one now and again
as I had a jar which had a slight darker crust/layer forming after about six weeks and smelt a bit musky but no
actual Paprika aroma. If I had a Deli nearby I would buy any tinned Spanish product.
I don't care about the science behind this, but instinct told me to bin it.
As well as my usual BIR mix powder, I make a second mix powder of freshly ground Coriander/Cumin
which has a wonderful nutty aroma on the day, but doesn't keep well, i.e used a few days later and it
didn't have the same effect on the dish.
"Your chewing gum looses its flavour on the bed post overnight"

cheers Chewy