Magura’s old stuff, forks (have some Wotans from new that were amazing once a few internals swapped about, and are still going on a back up bike), rim brakes etc.
Most folks problems are that bikes sold online/distance just come out of a box, then a random end user is using a torx for the first time (or just hammer a 3 or 4mm in there) and ‘tighter must be betterer’ kind of attitude = split master cylinder.
They have a bad rep for leaks too, usually hose/olive/barb/union type of leak rather than pistons crack n fail like shimano (again often down to end user hamfists), and many bike shops do not stock or even have access to the right parts from magura, instead jamming some shimano jobs in there, which are close, but not quite.
When working well, the e5/e8?? series of Magura 4 pots are epic, but many folk through in the towel before they get that far.
My only gripe with them is the 4 pots run very close to the disc, so alignment has to be several times better than most can manage. Many bikes need a proper facing before they go out with these brakes, any misalignment in the mount at all = infinite annoying pad rub