In the infinite wisdom that is Arfcom there can be only one answer.
Get both!
I have a Swift Trilyte 8x24 compact binocular that works great for sporting events, birds, bikinis and the like. And I also have a set of German B.Nickel 8x45 binoculars that my father hunted with in the 1950's in Germany. They still work perfectly, and are bright and clear. I use them when I'm hunting and glassing game at longer distances. I used them when I shot my first S. Dakota pronghorn at about 380 yards.
Never felt like I needed more glass. If it were me, and I could only buy one binocular, I would look for something in the middle like a 7x35, 8x35, 8x42 built on a mid sized chassis. The web is your friend. I did a quick search for 8x40 binos and got a ton of hits. Read the reviews, go to Bass Pro and look at their selection.
Steiner, Swarovski, Nikon, are good places to start.