I have had one set of vpowers and lasted me along time so far probably will buy my 2nd set sometime soon seeing its been a yr and a half since I have changed them.

 

i am one of them people... the copper plugs are cheap and work well even under high boost.... i replace my plugs once a year... maintance for me, i dont have to replace them yearly but i just do... and cost 10 dollars at a time...