Some ramshorn snails can be very pretty, colour-wise.
The larger ones certainly have much visual appeal to those who like snails.
Their feeding habits do contribute to waste management.
However...
Contrary to the snail propaganda machine, they will eat plants.
Whilst it's true they'll eat decaying and dying leaves, a snail's definition of 'decaying' or 'dying' is much broader than ours. Plants flex in the water and the slightest bit of natural damage is a dinner bell to a hungry snail.
Ramshorn snails, as evidenced by their prominence in those 'problem snail-infested' tanks, are prolific breeders. This is a factor that needs to be managed. Remember, they all start off tiny and then grow.
The coloured varieties appear to have been specifically bred, to appeal to the market, just as dwarf shrimps have now been bred into a variety of colourful strains. Just like shrimps, however, breeding different colours together will have the young gradually reverting back to their original colouration. Whilst shrimps may take several generations for this to occur, because of the proliferation of snail eggs and subsequent young, this colour reversion take take less time.
For me, Apple Snails are also a definite no-no, as this will munch on any plants, damaged or otherwise.
So it's the Nerites and only Nerites for my planted tanks.