I find them to be a bit clumsy and I prefer the sound of flesh on bass notes, especially a nice flesh rest stroke. I've divided my right hand technique into three positions that I use and it works very well for me:
The first is using my palm rested on the bridge for a palm mute sound, not always applicable in classical but great for blues and arrangements of pop songs.
The second is using my flesh of the nail with the hand only slightly elevated, kind of like a lute player. Good for older style music and such.
The third has my wrist rather high off of the strings, kind of like a flamenco player. This puts my thumb at a position where it's easier to use my thumb nail and can get the fullest sound from my fingers.
Kind of categorizing it a bit is helpful, I use a rather short thumbnail and holding it higher above the strings helps.