Benchmark has a lot of great capabilities and is an easy to use email marketing tool. It's pretty cheap and free to use until your lists grow larger. It's easy to get the job done with and offers excellent customer service. Their online 24/7 chat services are really one of a kind.
Very glitchy, doesn't integrate well with social media, doesn't offer advanced reporting capabilities, uploading lists can be a pain, and doesn't offer any interactive templates (gifs, flash, etc.)
If you don't have a PMS system to integrate to, massive company budgets or advanced email marketing campaigns - this tool is for you. Extremely budget friendly, easy to use and great customer service.
Our management company oversees 90 different hotels and it's a nice and budget friendly way to run campaigns for all our hotels without spam / cross interference issues. Benchmark also offers an excellent chat / help service which is quite helpful since the job has a lot of turnover.