I use mine (TC Harmony-M) very sparingly in combination with the S-950's reverb and it really adds to some songs. For the most part, it's not used in the vast majority of the songs I perform regularly. I suspect that it could be detrimental when overused, which some folks have the tendency to do.
Could I live without it? Absolutely, but I chose not to. It's a neat device that provides some diversity to a lot of songs, so I'll continue to use it for the next couple months.
Sometime about mid September I will be listing all the gear I will be selling, which is a pretty substantial compilation that includes one of my Custom, lighted Consoles with an attached Harmony-M and 9-inch display laptop, power supplies, etc..., all painted and shiny new - never used on the job - just one of my many backups. Can't have too many backups I always say.