ReloSwiss
Reasonable price, generally friendly service, nothing was lost or broken. There's no tracking service, so we had no idea how long it would take (with just under two months, it was about what we expected).
The only complaint is that the packers did clearly not try to save space, packing rather unsystematically and inefficiently (filling up book boxes with paper etc.). So while the final volume & price were about what we expected, we did pay for quite a bit of air/empty space.