If you really must have the best, the Ultimate Ears UE8 is hard to beat. It will run about $50.00 to have the kit formed to your ear by an audiologist. You send those molds in and they'll be built to conform EXACTLY to your ears and are incredibly comfy! This design also makes for incredible isolation. As for sound quality, they will likely sound MUCH better than anything you have in your home as they utilize an 8 driver system per ear. Most ear buds sound like an old AM transistor radio by way of comparison. If you want to jam a song, it won't be the mower that could damage your hearing, these things will reproduce music cleanly to very harmful levels...and sound perfect doing it at ludicrous volume, no breakup at all. But if you feel $2400.00 is a little too pricey for you, they also make an excellent 2 driver set that still sounds extremely good and will run about $600.00.
If these are a bit high for your budget, then Alien Ears would be my next choice. The G16 is an 8 driver custom molded to your ear and a piece of music nirvana! These are their top of the line and around $875.00 and worth every penny. They have a complete line up that starts around $200.00 so they have something to fit everyone's budget.
What is common with both brands is that you may think you have some nice sounding muffs or buds...but you really don't by way of comparison to anything about $350 and up from Alien Ears or ANY model from Ultimate Ears. And when you factor in they're made to fit your individual ear perfectly, the amount of noise reduction is just phenomenal! Many bands finds they need a directional mic facing the crowd and have the level set about 20dB down so they can hear the crowd between songs...they definitely have major isolation! These are touring ready, so they're tough and would work fine for anyone mowing.
