Your first and third phrasings are incorrect. To say "never better than either" means "always worse than both" (or, at best, equal to one of them).
#2 and #4 are both accurate, and logically equivalent, but #4 is convoluted—harder for the reader to parse.
So I would say use #2.
- A can never be better than both B and C.
The "both" makes it explicit. Virtually all readers will take it to mean "A cannot simultaneously be better than B and better than C". Which is what you meant. (Actually, your introductory sentence is "clearer than both #2 and #4" but #2 is shortest.)
"Choose either A and B, or C" means, in general, two choices:
"Choose either A or B, or C" means, in general, three choices:
If "C" is equivalent to "A and B",
"Choose either A and B, or C" gives no choice at all: it always means "A and B".
"Choose either A or B, or C" in this case means three choices:
And, in any case, the word "between" is superfluous in this construction.
Best Answer
#2 is correct (or more correct). #1 is incorrect (or less correct), but it will usually be understood by most listeners as meaning the same thing as #2.
In other words, this answer is a bit pedantic - most people will not notice or care about the difference, in most contexts.
This is correct:
(And you could use a different verb in place of the second "lead to": ...can either lead to energy efficiency or enable better space utilization.)
This is also correct:
The positions of either and or control (at least suggest) their scope.