If I am going to finish via oral then CIM is vastly preferred over BJ with a HJ finish. Spit or swallow doesn't matter much to me personally.
As to Jenny's question; I have heard that if the person performing oral is able to swallow while the guy is cumming it is apparently a different sensation (due to the suction and pressure changes as the repeated swallowing occurs). I have never had CIM or CIMwS that felt significantly different. I even had a GF try once we heard the story but it usually just ended up a bit more messy without any noticable additional pleasure.
I kind of feel the same way about DT. I think it's the visual that makes it extra for some. For me it's never been any great difference in sensation (it is different than not DT, but not some life changing penis pleasure I can no longer live without).
I also don't mind FK breaks during oral (giving or receiving). As I sit here typing and not particularly horny the idea of snowballing doesn't do anything for me, but in the heat of the moment... who knows. I've never had it presented to me (must be all the pineapple ).
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