Recommended bluetooth devices

My boss is a service manager for an air conditioning company. He doesn't need a hearing aid but he has a hard time hearing normal bluetooth devices in his truck. A few years ago he got the Blue Parrot B250XT and while he loves it, it continuously breaks down. We have sent in various units many times for RMA and have bought quite a few of them as well. He doesn't seem to physically damage them, they just stop turning on. He discontinued using the mobile charger as we thought that might be the problem but they still break. He never had a problem before with other blue tooth devices. Basically he has told me that either we are buying another one so he has a backup when he sends in the original for RMA (it's already happened twice this year) or I find him a new one that matches that over the head style with a loud speaker. Does anyone have any suggestions for other products? I have done research but I only seem to find cheap products. Thanks for any help!