I have a 2013 MCS with dealer installed JCW tuning kit. We also did a resonator delete. There is a super annoying drone on highway. Is deleting the resonator the culprit? I am just worried that if I put back on, it will change the exhaust note considerably. Maybe i just won't ever drive on highway. Hahaha

 

Welcome to the club!
Yes, you are right. It is due the resonator delete (it was under you seat)
If you want a nice sound (better than stock) you can delete the rear muffler and replace (install, in your case) a Vibrant UltraQuiet resonator.

Nice sound without headache

 

I have the JCW muffler that came with the JCW Tuning kit. I do nit think I want to get rid of that.

 

Sorry, my fault. I have not a JCW kit I was thinking in my justa while writing.

Just install an Vibrant UltraQuiet resonator in place of the deleted OEM resonator and it will be perfect.
Drone is present when there is nothing replacing the resonator.
I have started with a fiberglass (like cherry bomb) but that did not fix the problem.

 

Getting the one you suggest would be better than putting the stock resonator back on? I just do not want the growl, gurgle and pop to go away! Maybe I just will not drive on expressway, no? Ha

 

The magic with UQ resonator is that you will do not loose your pop nor gurgling.
I have some gurgle and pop when driving hardly and releasing the accelerator pedal abruptly. And my car should not do it !

It is not the same that a stright pipe, but you will not loose that behaviour.