If done right factory battery will last at least 12 yrs. I speak from experience.

Same here... I always disconnect the battery tender once it is fully charged. I hook it up about every 3 to 4 weeks.

Battery tender plus for the z and jeep

Battery tender jr for my gsxr

I've been using both tenders for years with no issues through multiple deployments. I keep the terminals clean and top off with distilled water on average 4 times a year depending on if I am home. There is no sense in having my wife run what she doesn't drive while I'm gone.