I haven't had too much trouble with eBays Global Shipping Programme
Same here. I recently sold two items which I didn't even realise were being offered under the GSP, and it was all completely painless for me: ship to a local Ebay centre, they take it from there and deal with the extra postage costs, etc. The buyers clearly thought it was OK for them too (One item was £30 with £4 local second-class shipping, so GSP couldn't have added much).
Ah, tell a lie, there was one problem: the buyer had requested a total cost invoice from me, and that apparently kills off handling by GSP. The fix (other than to have to mess with foreign shipping myself) was to cancel and relist, this time the buyer just paying the GSP invoice instead of hassling me for one