I recently sent a MIG welder via parcel2go, it was the worst courier experience i have ever had. The parcel was supposed to be picked up on the monday , I stayed in all day on the monday ( they tell you between *am and 17:30 pm pick up ) - no show, all day on the tuesday - no show, they finally picked up my parcel on the wed afternoon. I liased with the helpline all the time, however they kept giving me lame excuses and were no help at all. Luckily because i mostly work night shift and 4 on - 4 off i was able to accomodate them, i would have been well pissed off if i'd taken time off work for this though. When the young lad did finally arrive to pick up the parcel he was off-hand with my wife, luckily i was out, he soon changed his F**king tune when i answered the door the next day ! In fact they actually turned up on the next three days to pick up the same parcel ! (Piss-Up and Brewery instantly spring to mind here.......)
My advice, use the Royal Mail, you might have to pay a little extra but its worth it. Also my own personal experience of sending parcels is plan for the un-expected. Make sure your item is well padded insideand that it cannot move around inside the container and that the container is strong enough to withstand rough handling, including being dropped.
Don't just put one address lavbel on it. Put 2 or 3 including an independant return address label on different sides of your box. I also write at least one address using a marker pen and then put clear packing tape over it, so it can't be rubbed off.
Any items that i have ever recieved that have been damaged or lost have been due to inadequate packing and addressing ( one guy sent me a Linn Axis TT but forgot to put the address label on !!!). I have sent quite a few delicate items through the post with no problems, including TT's, Cartridges , etc. At work I also often have to send expensive Aircraft parts around the world, some of which have price tags of over $100,000, at this kind of money chances can't be taken...