Imation security software - any good? alternatives?

I've been playing with Truecrypt in my spare time, but have hit a snag. To run on a USB drive, it needs to be run as 'admin' or needs to have Truecrypt already installed on the host computer. This presents a problem, as neither option is open to me at work.
So, the next option for me is the software that came on my Imation 4Gb clip drive, called ImationLOCK. It works, both at home and at work. My question is, how good is the security? The documentation that came with tells how to use it, but doesn't say anything about what is being done to protect the data, i.e. is access merely password protected, or is the stored information actually encrypted? If so, encrypted with what algorithm?
I don't need it to be as strong as Truecrypt (which I would call industrial strength encryption), I just need it to be decent (read: not easily bypassed/defeated).

Anyone know how good Imation's ImationLOCK is? Or, anyone know of a free alternative to Truecrypt that doesn't require admin authority to run on a USB drive?