After my Battery Tender plus died last year I replaced it with a CTEK 7002.
CTEK make some of the most advanced chargers on the market. I like the $90 7002 over the smaller $55 3300 because it has a desulphation mode which will recover slightly sulphated batteries.
Straight lines are for fast cars...turns are for fast drivers
'04 M3 - track
'06 650i Cab - daily driver
'02 Highlander - kid hauler
'01 330Ci - winter beater