I had a set of the standard Flare Calmer's for a year and they absolutely became an essential for me. If you're wondering about any of the Calmer products I can say that when I first put them in, I wasn't expecting much. They don't have that immediate noise blocking of other plugs and so when I first used them at work I was open, but not expecting much.
Fast forward an hour later and I take one out to adjust and my god the noises that I could hear! I realised for most of my working life my brain has been actively filtering all this noise and it's been costing me. With consistent use I noticed that I no longer had that constant low level anxiety, and I felt relaxed and comfortable when before I'd always have this underlying desire to just "flee" somewhere else for reasons I didn't really understand.
I used my Calmers so consistently that I now have probably trained my brain to chill the moment I put them in. One problem I always had was fit. I think my ear hole is a bit larger than most and so the plugs sometimes went in too far, causing some itching and discomfort at times. The benefits were enough for me to put up with it happily, but I when I saw the Pros on offer I immediately purchased.
The pros I think do have a little more effective noise blocking, and psychologically they have slotted right into that role that I established with my standard Calmer's. The main difference though is the fit is much better. With the extra rigidity they don't sink as far in and so though I think they're technically the same size they are more comfortable than the more flexible model. I would recommend either type to start off, but note that if the standards seem too small, you may benefit from getting the Pros.
