Less expensive than a new bike lol but yeah everyone has to make their own cost/benefit analysis.

I just bought one & it is surprisingly light, I barely notice it in my jersey pocket. I wouldn't use it to leave locked up overnight, & the manufacturer even says it's for short duration use, but I live in a reasonably low crime area & it gives me peace of mind to deter crimes of opportunity if I want to stop for a cup of coffee or lunch or whatever.