I will just toss in my experience with the Shorai.
I had to replace the AGM battery in my '07 Bandit 1250 last summer after I left the key in the wrong postition and killed it. I decided to go with the Shorai, not so much as dropping a few pounds from the bike, but because it had a slower discharge rate when sitting.
The Bandit is not sitting where I can plug it into a battery tender and sometimes goes weeks without being ridden.
After sitting untouched since before Thanksgiving, I went outside and started it around the end of January, and started as good ever. It was around 45 degrees at that time too.
I actually let it run for about 30 seconds, turned off and started right back up with no problem. I know the cost was alot more than AGM, however being able to let it sit for a while and not needing a tender was worth it for me.