I've been using the
ACS ER15s for around 6 months. I'm very pleased with them. The noise levels are much reduced and you can still hear speech and radio communication headset on or off and using the speaker. They stay in for the walkaround and it's possible even with the brake fans running. One bonus is that I find my fatigue levels are much better: less noise is simply less fatiguing. Even now, when I take them out at the end of the day, I still can't believe how noisy the ventilation fans are!
I got mine via Boots. Go to a larger branch of the Opticians and make an appointment with the Audiologist who will take mouldings of the ears and send it to ACS who send the hearing protectors to you.