I believe that half the mystique of the Whitworth was derived from its initial uncanny accuracy, by the standards of the day. Certainly, harassing fire, sufficient to cause fatalities, became part and parcel of infantry-v-artillery during the Crimean War, when one astute young British officer gathered a bunch of his best rifle shots, using the new-fangled Pritchett-bulleted rifles, and played merry hell with Russian gunners over half a mile away, driving them from the field.
However, the rifle of the day was not quite good enough, shooting that huge Pritchett/Minié bullet, for the very best of accuracy, whereas the Whitworth plainly was, as proven in comparison tests at extended ranges.
And then in the American Civil War, their usually-fatal use on selected targets brought a new dimension to the battlefield, as Messrs Reynold and Sedgwick, and no doubt more than few others found out to their cost. Even at 800 yards or so, the danger zone of a well-aimed Whitworth rifle was sufficient to make standing still in full view a final act. General Sedgwick was even advised to move along, as that every officer who had stood where he was standing on the previous day had been killed or injured...half a minute later, that fatal dull thump was heard.
Back to the present day and in America, where the Civil War is not only endlessly reenacted, but discussed and argued over on a daily basis, there are a few actual physical survivors for those awful days in the form of actual Whitworth rifles with provenance of use - fetching not tens of thousands, but hundreds of thousands of dollars to collectors and very lucky [and rich] shooters who care to load and fire these incredible relics.
For most of us, a replica is the nearest that we'll ever get to one, not that they were exactly replicas in the first place. True, rifles from the 'lesser-known' gunmakers who 'borrowed' Whitworth's idea of hexagonal rifling - Kerr, Beasely and maybe others I wot not of - can sometimes be found in the USA, but the real thing, with that famous sheaf of corn trademark, will always be very special.
I'll note that, in my opinion, the Parker-Hale Whitworth-rifled match rifle has never been equalled, and it should be eagerly sought-after. The johnny-come-lately products of Euroarms [Dixie] and Pedersoli can also be good products, although there have been vague mutterings off-stage about the fit and finish of the Pedersoli product from people posting here, and on yotube. Note that the new Pedersoli rifle will certainly be more expensive than any Parker-Hale I've ever encountered, here in UK or over in the US or Canada.
This rifle, BTW, is forty-one years old.
The buyer is the final arbiter.