My take on the Whitworth is that it is actually slimmer, lighter, overall more compact and more "English traditional" looking than the CZ. Nicer wood on the stock as well. I also like that it is a pure Mauser copy not a "modified/improved" version like the CZ - and I am a huge, biased CZ die-hard fan. Just like the firing pin assembly and triggers on Mausers better than the ZKK/CZ 550 versions. This applies especially in .375 H&H. But as other suggested, for a .458 Lott, I'd go with the CZ550 or I would find ZKK 602 in .458 WM and have it re-chambered. My Whitworth needs no slicking up, it is slick from the get go. But then again, so are and were most of my Brno/CZ rifles. In general all actions get slicker with use.