I've had great success at using these < http://www.lacie.com/products/product.htm?pid=10821>.
Some people will rubbish them, but having sent around 30 of them to individual clients all over the world I've had no issues.
As far as the postal/courier service go's, I don't believe there is any difference in the Quality of delivery unless you use a consigned document specialist, but very expensive.
Be sure to pack the drive the same way it was shipped to you. If you really want to be careful, put the drive box inside a larger box and surround with packing peanuts.
Be sure to keep a backup at your shop until your client receives the drive and confirms the data is good.
As for drive recommendations, we use G-Techs. I have used LaCies with no problems, but stopped after hearing too many horror stories.
MacPro 8-core 2.8GHz 8 GB RAM OS 10.5.4 QT7.5 Kona 3 Dual Cinema 23 ATI Radeon HD 3870
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Final Cut Studio 2 (up to date)
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