Kimberly:
Well, since I am natural I cannot really plead knowledge of how a cut penis feels. I have certainly read posts from men who were natural and then were circumcised for some reason and testified that they did in fact lose some sensation in the glans after a while, probably the result of the toughening that would come from contact with underwear. I know that if I inadvertently put my penis back in my underwear with my foreskin retracted it feels quite uncomfortable. In fact I would go so far as saying that the only time my glans does not feel somewhat uncomfortable when exposed to the air is when I am sexually aroused (at which point sexual sensations of course take over and mask ordinary sensation).
Clearly circumcised men can perform sexually, else, how does one explain where all the Jews and Muslims came from? (Joke, BigK; not a slur on religious folks of any denomination.)
With respect to "the robbed of feeling" part of your question, I can only say that I can definitely feel enough sensation in my foreskin to ejaculate by manipulating it alone during masturbation (as I recall I did quite a bit during adolescence in particular -- in fact I used to test myself to see how little touching my foreskin needed before I shot). Furthermore I can definitely get aroused by merely tickling my foreskin, i.e., not using it to stroke my glans (although that is the better way to excitement). Also, I have read several times that 30% of the nerve endings of the penis are in the foreskin. Based on the types and intensity of what I feel that sounds about right to me.
As for the preferences women have and how the two types of penises are judged during sex by them, I can only repeat what they have told me. Most have expressed a preference, but only after a while (of having sex with me). Two that I can recall said they strongly preferred a natural penis to a cut one, but both had limited experiences with other natural penises (since when I was growing up in the US the large majority of boys were circumcised; I once asked my mother why I was not and she told me that it had been her decision, rather than my father's, and that it was because men in her side of the family had not been circumcised and that she considered that since the foreskin occurred naturally it was there for a purpose and she was going to darn well not mess with Mother Nature [or words to that effect], plus I "looked better" that way; that was the only time I discussed the matter with either parent). I should point out that I never pressed women for an evaluation of my penis vs. cut penises, but rather they just volunteered them, I suppose because they rarely experienced natural penises otherwise.
One final point. There was a period in my life when I lived in and spent a great deal of time traveling to and from Asia. When I did I used to regularly get massages in my room from the hotel masseuses, a service almost universally available in that part of the world. Even though most of these women were not professional sex workers, in fact most were part timers augmenting jobs as teachers, secretaries, clerks and the like, they always offered masturbation at the end of the massage -- for an extra fee, a "tip". I had hundreds of these massages during that period and many conversations with the women. It turned out that several told me that in general men with foreskins came more quickly than men without unless the masseuse slowed her stroke or used other devices (e.g., tickling the perineum) to prolong the pleasure while elongating the process. And since they were being tipped in some degree by the pleasure they provided they wanted to prolong it as much as time allowed. They also told me they could offer a powder massage or even use no lubricant during the hand job if I preferred, something they did not offer cut men. In both cases I found it a better hand job, and some of these women were extremely skilled indeed*.
(*As an aside I might add that these women were a story unto themselves. They were quite ordinary women as I said, not professional sex workers and certainly not prostitutes. Masturbation was the only sexual service they offered. Most were young or youngish, ages from early 20s to late 30s, married (though a few very young ones were unmarried and claimed to be virgins [and I believed them]!), and doing a job that offered good money and a little sexual excitement without their husband's knowledge. Some had been doing it for many years and so, just doing the math, had probably done thousands of hand jobs on hundreds of men by the time they were in their late 30s. (They averaged two massages a night when they worked and they worked 3 or 4 days a week, I learned from discussions with them.) So they were quite knowledgeable about penises, masturbation and ejaculation rates.)