But still a better option than nothing at all i would think?
I think so and have had one on my last two bikes. You could pry it off with some effort, I suppose, but that takes time and makes noise, so I agree with an earlier poster than the would-be thief might just go elsewhere and look for easier pickings.
Seems like a lot of people are having problems with the HD lock and it's really expensive. This could be a good alternative and there is an option for tamper-proof fasteners. Two-pack is $30. I'm about to order one myself.