I've got motobatt in all but 1 bike, I always fully charge a new battery before installing. My bikes each would also only do a couple of thousand km's a year the oldest battery has been in since 2011. I also periodically give each battery a day every couple of months on a trickle charger. The one bike that doesnt have a motobatt is the one that last week didnt have enough oomph to start the bike, this initiated a round of charging for all the bikes.
Another long winded reply for motobatt oh and any charger should work