I'm not going to disagree as I've got no experience of custom moulded ear plugs.
All I can say is that I use
these and find they are very, very effective at cutting out noise even at silly speeds (on a private track m'lud), but still enable me to hear what's going on around me.
I get through one pair a week doing about 500 miles. I last bought a box of 200 pairs, which works out at just under £20 for 100,000 miles of biking. Should be good for a while then
Someone mentioned earlier that fitting them correctly is essential - of course they're right. I do the usual and roll them up to make them a bit slimmer, before looking like a tw@t and using one hand to lift the opposite ear upwards and straighten the old ear canal ready for insertion. Give it a good shove in there - don't be afraid
This works up to a point but I also found the length of the plugs meant they popped out a bit and didn't create an effective seal when they expanded. To solve this, I nip about 2mm off the bottom (narrow end) of each plug with a pair of scissors and jobs a good'un
Works for me. May not work for anyone else but hey ho.
If you're still reading this, move on