I have the Makita 9565cvl, awesome bit of kit.
We sold loads of those but for some absurd reason Makita stopped making it last year and replaced it with the SA5040, which in a word is garbage.
If you want a dedicated polisher (you already have a grinder) then the FLEX L1503 (1200-3700rpm) is the way to go.
If you don't have a grinder and want a more versatile machine then the FLEX L1506 (2200-6800rpm) is the way to go.
Same machines, different gearbox. German made, Flex invented the angle grinder. They are the brand of choice for stone masonry.
When buying a variable speed machine, buy something that is going to be operating towards it's upper speed range. Variable speed machines (whatever brand) don't like extended periods of use at their low speed. It's like a car sitting in traffic on a hot day, they tend to overheat a little.