I like that it is easy for non-technical people (like myself) who are not marketers or writers etc to use! It's also really good at automating my outreach process so there's less stuff sitting in an email folder waiting for me to reply when i could be working instead :) The free version isn't great enough if you're looking to do anything beyond just sending out occasional cold calls - but they have tiers with different features which gets better all the time.
If you want something super cheap then go for the trial first before committing money up front because otherwise we'd probably lose our customers by now ;) We've found using this tool has made us look professional as opposed to being stuck in Gmail drafts forever.