"The Mauser 98, and all its variants, was in use on 4 continents by more armies than you can come up with quickly. The SMLE was in use by British Empire forces (Commonwealth later) and no others I can think of."
Scorch,
On its face, that might seem to be a valid method of assessment, but I think it's not.
There's a very CRUCIAL difference that has to be taken into account.
Mauser was a commercially developed and made rifle, which was then licenses to other nations.
The Lee-Enfield was not. It was made by the British government at its arsenals and was never licensed to any other nation.
Any nation on the face of the earth could call on Mauserwerk and say "We'd like 100,000 rifles in XXX caliber made for our army, your assistance in building a factory in our nation to make subsequent rifles, and a production license that allows us to build those rifles in our own nation."
That never happened with the British, as they never offered that sort of commercial option to nations outside the commonwealth.
That Mauser did arm many possible German rivals apparently caused some concern in the Germany government.
Once again, though, the issue is what rifle was the best COMBAT rifle. It's already been shown that the Mauser falls short in several combat categories -- speed of action and magazine capacity being two.
As for the Lee-Enfield's performance in South Africa, much of that can also be attributed to tactics of the warring parties, not just the rifle. To that point the British had never encountered the kinds of tactics used by the Boers and were ill prepared for them until they got a couple of forward-thinking leaders into the field.
The British drove the Mauser-weilding Boers into submission, and the British used the experience and made a number of modifications to the design, including the addition of charger lips on the receiver bridge, to allow faster reloading.
Don't forget, also, that the standard Mauser in German hands was also redesigned a number of times. The K98, with it's rifle length and straight bolt handle, eventually morphed into the K98k with its turned down bolt handle, for example.
If, however, you want to look at ultimate outcomes, in two general wars, the Lee-Enfield was on the winning side, the Mauser on the losing side.