Nsok, to show just how subjective FELT recoil can be, coupled with the effect of being fired from different platforms (remember, these are my personal impressions of recoil based on rifles I have/do own, and others I have fired);
1) I find any of the three different 458 Lotts I have owned to be more comfortable (easier on the shoulder) than any 416 Rigby I have ever fired (full power 416 loads come back much faster than the Lott which is more of a heavy push, than a fast kick)
2) several different 470 Nitro doubles I have fired to be slightly more comfortable (easier on the shoulder) than my full power loads in my Lotts (most of the double 470's I have fired have been very generously weighted at 10lbs and more).
3) my light-weight Rem 700 mountain rifle in .375 H&H extremely comfortable to shoot, more so than a CZ 550 I have in the same calibre that weighs more than a pound heavier (the stock shape and dimentions of my Rem are ideal for me as compared the the Cz stock).
4) most .375's to have been more comfortable (easier to manage) to fire than the, two only, .300 Wby's I have ever fired.
5) have noticed a trend of felt recoil, (on me at least), that cartridges with sharp shoulders, e.g the Wby range, will tend to produce more felt recoil than counterpart tapering rounds. Personally, I find it easier to manage the recoild from a well stocked .338 than firing a .300 Wby.
From my personal perspective, the main factors which appear to have major bearing on the level of "recoil-impact" on me when firing;
* projectile weight X velocity
* stock fit/configuration
* muzzle blast
For me personally, (I have substantial hearing loss, a direct result of exposure to repeated muzzle blast) I experience some 1/3 less (as close as I can judge) actual felt recoil when using hearing protection as opposed to when not.
Proper stock fit and familiarity will go a long way to "taming" felt recoil in big bores but I concede that we all have our individual limits.
I guess I was fortunate, in a way, to have grown up as a young lad accustomed to firing great volumes of 12g rounds at frequent intervals.
These days, after having fired many hundreds of rounds of 458 Lott ammo in the field and over the bench that, for me, knuckling down on the bench with my favourite .375 has become rather mundane and uneventful.
I conceed that there will be many that dissagree with my "perspectives" as I see many different hunters in the field each year, of different shapes and sizes, firing different rifles, all essentially chambered in the same range of big bores, .375, 450/400, 404, 416, 458, 500 and most all displaying different levels of managability and control over the recoil produced in those rifles.
Not much help to you I realise, as I understand from your post you are trying to gauge your ability to cope with the level of cartridge you intend buying.
My suggestion would be to try and find the best fitting rifle in that cartridge, find someone who owns one and test fire it (with moderate loads) off-hand, or from shooting sticks whilst wearing proper hearing protection. If you find that you are able to have some reasonable level of managability, understand that altering the stock of your chosen rifle to best suit your fit, and plenty of familiarity with that rifle will eventually lead to dampening the effects of that recoil.
Also remember this, we have a higher portion of one shot kills on buffalo from hunters placing their first shot well with a comfortable .375 than with all the other cartridges combined !
Sorry for the long winded reply but recoil is a constant factor in my life for both myself and my clients, and although I am aware of, and acknowledge, that not everyone will ever be comfortable with the likes of a 458 Lott or a .500 nitro I believe there is a lot of "whooey" out there written about recoil that prevents some hunters from ever realising the wonderful benefits provided by some of these cartridges when the correct procedures of rifle fit and familiarisation have been addressed.
Paul.