has anyone ordered markers from them in the UK? and is so did you get stung by customs?
I haven't
But that would cross the threshold and import vat will apply (depending on value import duty could get added to higher value items)
The thing that hurts is the courier handling fee.
If customs fees are due your don't pay to clear customs, the courier handles it all and charges an additional fee to you - anything from £8 to £20 depending on the courier, not the customs amount
Unless it's something special buy in the uk. If it is something special then have a word with the uk retailers and they may import it for you, often resulting in a net saving because of the way customs clearance fees are handled for companies