I'd go a little at a time, you need the comfort, but also need a snug fit for the best sound.

Wireless would be nice, but i'm still on the cable and my original helmet, this setup will carry me thru the rest of my ridding days.

 

 

Can you plug in earbuds? I use shure in ear monitors. Drawback is it isolates outside noise, upside is they sound fantastic.

 

I am having the same issue, I do not want to cut into my helmets. I discovered that J&M now have a headset with slim speakers, but they are pricey. I have sent an email to IMC asking the diameter of their speakers, assuming the sponge donut can be removed.

 

I currently wear a Shoei J-Cruise and have Sena headset speakers which do not create a problem with my ears (which are freaking huge, btw). In the past, I have had to modify the speaker recesses to make them usable, but in other helmets. What I have done and wonder if you can with the Shoei is depressed the foam at the base of the recess with a tool (like a spoon) to create a deeper recess. I am not sure this will work with the Shoei, but it has with other helmets for me.
I think the reason I did not have to do it on this helmet was I finally decided to try a larger size and it is way more comfortable, especially with my previously described large ears.

 

My helmets are scorpions and they have a hard molded plastic for the speaker recess.