personally I love it but like Lucy it can take a while for me to cum and so I usually tend to stop the guy when he's givin me a good licking cause im aware of the limited time we have together and my ultimate goal is always to make him enjoy himself and cum,however nothing makes me hornier than knowing that a guy wants to go down on me and make me cum and so I end up just wanting to tear his clothes off and get at him
on the flip side some guys dont have a clue and end up hurting me but if thats the case subtle tilts and movements usually guide them in the right direction.also the best way to know if a girl has really cum is if she gets really wet all of a sudden and if her ahem 'canal' tightens and lossens really quickly but thats not for all girls so really you never 100% know.......sorry