I fly regularly and I can tell you trying to put something like that in your luggage is a sure way to have your luggage held and possibly be denied boarding on an international flight.
Definetly not worth the hassle!
I had my luggage held for 24 hours once for a portable hard drive in my checked luggage, no reason given for the delay...I just had to wait until the next day to receive it. I was told my luggage was put on another flight.
When I picked up my bag my hardrive had obviously been disassembled (screws were hanging out and loose) and the drive was wiped and unusable, there was nothing on it but copy's of my own personal music (which I legally paid for!) and work files (PowerPoint presentations) etc. since I like to have my music on the road and the company frowns on me putting it on my work computer. This was on a non-international flight.
I can't tell what they did to the drive but I assume it was wiped with a very powerful magnet since its unformattable but works fine otherwise. From that day on I put my portable hard drive in my carry on where I can watch it, there is nothing illegal on it but the airlines could care less about your personal property. Luckily nothing on there wasn't backed up somewhere and I was able to find everything again (music is backed up in three different locations) but I was suitably unimpressed especially since they lied to me about the delay.
Ship it FedEx, they don't even check those boxes...just don't declare it as dangerous goods or you will be royally reamed for the shipping charges. List it as a residential pool test kit and let them figure it out, it will probably sail right through.
