In my experience, such devices ("dongles") serve only as a challenge to hackers and a major inconvenience to serious customers.
I would certainly regard a dongle as a big minus point when considering a system for purchase, or for recommendation to a client.

Even devices from sources experienced in this dubious art can be a real pain in the proverbial - I would therefore recommend that you should not attempt to "roll your own" - buy one from someone who's already ironed-out the BIG bugs!