Most people seem to focus solely on one vs. the other, but I'd imagine many people want both. Can you train for both of them adequately? For example, train to get bigger and maximize muscle size; but also train to get stronger and be able to lift more weight and have more overall power too.
I follow my own routines which work for me, but I can't comment on how "efficient" they are for anyone else -- and I can't say they're positively the best method for me either. Basically, here's what I do:
I set aside one "brutal" day -- that is, a day where the muscles are worked very, VERY hard. I combine higher reps with lower weights, and higher weight with lower reps -- and often go to failure or beyond. I do not limit reps and go anywhere from 1 to sometimes 50+. I basically combine elements of power, strength, endurance, and hypertrophy in to one workout as feasibly as I possibly can.
I notice results, but they're not very fast -- but that could be just the way my body is. No workout is "perfect" -- people often have to find what's the best their body can do. I believe my body can't do much better, so I generally stick to what years of experience and reasonably acceptable results gets me. So, back to the point, can you have the best of both or "all" worlds, or am I going at it the tougher way? I don't care personally -- I just want to know if doing both is more efficient or not. I know I can make heads or tails either way since I'm dedicated and motivated enough to accomplish anything.