In my experience dealing with super expensive aircraft batteries, dealing with battery gurus and having them recommend Battery Minder over Battery Tenders that's the brand I use.
I have one of these exact same model. Bought the optional cigarette lighter adapter.
Switched the fuse location up front on the Spyder to make the trunk power outlet full time live.
Connect the Battery Minder with the cigarette lighter adapter on that power outlet after each ride.
I have used Battery Minders on the aircraft batteries and doubled the expected life span or taken failed batteries and let the Battery Minder desulfate them and have them last another year.
This is the one I use for the Spyder or cars / trucks. Not too expensive normally but better when on sale. $43...
http://www.northerntool.com/shop/tools/product_200589669_200589669
PK