I installed a lithium battery in my 1999 Dyna. The motor has been hotrodded a bit, and the standard AGM batteries would struggle to turn it over at times. I'd been toying with the idea of installing compression releases, but really didn't want to pull the heads and go through getting the machining done. This battery spins it much faster and it fires off immediately.
I've wondered about the lithium battery and if it was worth it. My engine has compression releases but still struggles sometimes.
I have a CVO with HD's big bore kit so it's a 117" engine now with 10:1 compression.