Well I think both bare and clothed underarm tickles are hot and really neat, though I prefer bare underarmed tickles when I am a switch/ler or lee to be honest and sometimes playful underarm tickles on the sneak is good and lots of fun too but more like to know whether it is going to happen or not-that way I am mentally and physically prepared when a switch/ler wants to tickle my underarms. I more prefer the soft gentle tickles on my underarms or when I am being a ler and dishing out the tickles. I don't go and don't care for pinching or prodding tickles on the underarms to be honest.
Soft tickles, a soft fluffy feather feels sweet and feels nice gently tickling the underarms and also along the arms slowly and slowly tickling the inner arms too, that is neat that is hot. Also a stiff feather tickling the underarms feels good too and very ticklish sensation also. Also gentle fingertips gently gliding and tickling feels good also.