Wanted to vote but if I had to choose 1 only. It'll be hard.

Up till now my experience with Poslaju & DHL is great. DHL might be more expensive on one side but it just took around 2-3 days for my stuff to be sent out overseas.

As for Poslaju, I always use them so up till now, nothing much to complain about them as it's cheaper. The only complain would be they might need to speed up their updating style in the site. Too slow sometimes in doing the updates.