the second @12 versions are pretty bad because they are a mod by someone, and have no rubys in some spots,
the latest version have stones on all transfer gears
In general, the high beat standard layout with 6/9/12 are very good when you are nice to them. You just need to follow the rules for setting date and you need to know the basics on how to operate a chrono. The 6/9/3 layout is also very good, but you have the sunken DW problem. Stay away from the Daytonas with the A7750 movement, the transfer gears do not have any stones / diamonds and they run on metal, it is just a question of time when they stop working.
Regarding the low beat, I never bought one and I hear people being happy and other people are not happy.
I have a Breitling with the standard layout, it was serviced right from the beginning and it is running now since 4 years with +1sec / day.
Ziggy said, the build quality is very good for a A7750 and after a service the watch will run a long time until it needs service again.
Also the A7750 come with different grades and most of the time they are dirty, over oiled or haven't seen any oil, that is the problem. For example, the first HBB fab used only top grade A7750 and I have a friend and his HBB is 3 years old and running very good without a service.