Need new shower/tub mixing valve

Well 20-20 hind-sight I would have had the mixing valve replaced when I redid the shower
But it was not leaking at the time - 2004/5
A new Moen cartridge a year later stopped a small drip (2005/6 ?)
It started dripping again - off & on, now its pretty steady

I do have a whole house filter to prevent sediment thru the lines
I should have had the plumbing reworked & reversed the tub
The opposite wall is a closet - plumbing is on an outswide wall
Maybe in another 5 years I'll redo the bath again & have a plumber reverse the pipes/drain at that time

So I need a new mixing valve & really don't want a low grade model from a big box store
So what's a good brand to buy



Bath was redone, cement board & tile
The surround was in rough shape & leaking when we moved in
So I didn't want to let water damage continue
It wasn't as bad as my last house, old pic from before renovation:

If you bought the cartridge at Low*s just go get another and return that one...it should have lasted longer than that....

I have no faith that the valve has not been worn out
I put the whole house filter on after we bought the house
Almost every other fixture in the house has been replaced

As a test I shut off the HW feed to the shower
The leak stopped
So not only a water waste, but am energy loss too
The old water heater rusted out shortly after we moved in
So pretty sure rust went thru the piupes & messed up the valve
Since then both toilets are new(er), bath & kitchen faucets too
One toilet was getting sediment