A long time ago I did a earplug shootout where I got two sample packs of different earplugs from the USA earplug superstore.
Comparing two dozen different style and makes I came to like the Howard Leight Pilot best. This is a non roll foam ear plug, the design solving the main issue I had with foam ear plugs for years that they were often impossible to get properly seated in my ears. The non roll type you simply push in gently and they are very comfortable to wear. (Since then I have seen the MotoGP riders simply apply a spot of saliva to their foam earplugs and push those in which I tried and works)
The other thing I liked about the Pilot ear plugs is they have a NRR 26 rating which is the amount of sound the reduce. The top industrial ear plugs have a rating of NRR 33 and that gives closer to total sound isolation but the NRR 26 rating still allows you to hear cars around you and your engine but cuts the wind roar that causes permanent hearing damage in riders and which is also the source of fatigue when touring.
Unlike some foam plugs these can easily be washed and reused and a small amount last a long time. I recently ran out and decided to try a new version of the non roll ear plug from same company, the model is called Quiet, pictured below in orange and an old pair of Pilot’s in blue. These new ones have a more firm body to them, the Pilot was ultra soft foam. The Pilots will occasionally break seal when riding and that is a weak point as you may be tempted to ride on rather than stop and fix. The Quiet once inserted stay put and are lower profile designed to not interfere with helmets for riders. NRR remains 26 and you can get them in small cases which clip onto belts.
Personally I find the old model more comfortable to insert and a little more comfortable to wear but the new ones being slightly more firm offer that more reliable seal which is a good thing since I have found myself riding on at times when on a expressway with one of the Pilots slightly loose and allowing some wind noise which end of day had some ringing in ear thus some damage done. The more durable material also means each pair will last for ages if washed and stored carefully. If you are super sensitive to ear plug comfort the silicon soft swimmers plugs are your best bet followed by the softer Pilots and the Quiet I am only recommending for people accustomed to wearing ear plugs already but so far they seem suited for riders.