Really depends on the situation. If I were to pick one or the other I expect it would be rest strokes 80% to 90% of the time.
I play very close to the strings with both hands. I mute with everything I have available and seldom lack contact with the strings. As such I will almost always end my stroke with that finger resting against the next string even if I am going to hit it with another finger shortly after.
It's just my habit to cut notes very short (or at least be in a position after the stroke to accomplish a new mute with that finger or thumb). As far as the thumb that also is mostly a rest strokes but obviously you can work into the up and down on a string and, unless you are doing a double thumbing kind of deal, you don't necessarily have to rest on the next string prior to coming back up with the opposite side of your thumb.
Again I don't present myself as either an instructor or even any kind of expert. Just someone who uses this technique and sees a lot of benefits in its use.
Spin
I play very close to the strings with both hands. I mute with everything I have available and seldom lack contact with the strings. As such I will almost always end my stroke with that finger resting against the next string even if I am going to hit it with another finger shortly after.
It's just my habit to cut notes very short (or at least be in a position after the stroke to accomplish a new mute with that finger or thumb). As far as the thumb that also is mostly a rest strokes but obviously you can work into the up and down on a string and, unless you are doing a double thumbing kind of deal, you don't necessarily have to rest on the next string prior to coming back up with the opposite side of your thumb.
Again I don't present myself as either an instructor or even any kind of expert. Just someone who uses this technique and sees a lot of benefits in its use.
Spin