For foundation brushes, i mix it up between Chanel and Trish.. depending on the foundation.
For liquid eye shadow Laura Mercier has a great brush . I also love to use Bobbi Brown's gel eyeliner soemtimes and when i do , i use their gel eyeliner brush -- which really is amazing..
For every other brush i am 1000% loyal to Trish Mcevoy. I clean my brushes often and hers have lasted me years and years. However, i do find myself having multiples of the same brushes because of just how amazing her brushes are. The allow the perfect amount of pigment onto the skin and are the softest brushes out there -- and believe me i have tried most if not all. I am what you would call a product junkie so i feel as if i have done enough "research"