I had some 8X56 Swarovskis that I loved. Someone else apparently liked 'em better; he relieved me of them without my knowledge. So, I replaced them with Zeiss binocs in 10X56.
(1) Warning - be careful of Zeiss! (Yep, you read that right.) The binocs I have are those with the pull-out eye cups cut at 90 degress to the axis of the lenses. (The new ones I belive have angled eye cups.) Mine have been an utter failure. Once outside temps get down to the point that you start breathing steam, the binocs fog within 5 seconds of when you put 'em to your eyes - yep 5 freakin' seconds. I have tried every way to eliminate this problem, including sending them back to Zeiss, all to no avail. If I take off my hat, tilt my head up at 45 degrees, and back off the binocs until I can just see the objective inside the black ring that's created, I can maybe stretch it out to 10-15 seconds. In short, these are about as useful as a paperweight in the field.
(2) Power - I had better results with 8X for long-term observation and scanning. With 10X, you'll find that it's harder to hold stabilized, and after awhile, you'll get a headache unless you use them on a tripod or some other firm base, and of course that's impractical when scanning.
Best,
Jon