hands down, get something from vortex. for the money, they cannot be beat, especially since they come with an unconditional lifetime warranty. part of my job is selling binoculars, so i compare different brands every day and i will tell you now that vortex is outstanding. they have a good range of quality and prices. unless your going to spend 2 grand, i honestly dont think you should get anything other than vortex.
www.vortexoptics.com
10x50 is a pretty good size to go with for a lot of activities. but that is only if you dont mind the little extra weight and size that comes along with them. one thing you have to know is that having a 50mm objective lens over a 42mm does not give you a wider field of view, but only more light transmission and a little better clarity. that is a big misconception. going with an 8 power over a 10 gives you a wider field of view and better light transmission with the same size objective lens. also, you can hold them a little steadier, but most people dont have a problem holding a 10 power steady.
there are three models i would recommend that are awesome without breaking the bank. the diamondback (10x42=$229.99) fury (10x42=$299.99) viper (10x42=$549.99).
the diamondback line are affordable for just about anyone looking for a good quality optic without spending too much money (to make the wife happy if anything, haha).
the fury is essentially the same as the diamondback with a couple minor advantages. they are built a little tougher and have silver coated prisms which helps increase light transmission through the prisms. one nice feature is the diopeter (right eye focus) is right under the center focus wheel, so your fingers hardly have to move to quickly adjust your focus.
the vipers are in a league of their own to be honest. they are incredibly lightweight and use a higher quality glass and phase coatings. very durable and easy to look through. they are also slightly more compact than the preceding models. the vipers contain vortex's xd (extra low dispersion) glass lenses which help with light transmission and clarity, especially in low light conditions. they also use they're xr phase coatings to provide maximum light transmission and detail. they have a locking diopeter so once it is set it stays there. one really nice feature are the metal reinforced eyecups. (if you've ever heard anything about the nikon monarchs, it probably had something to do with they eyecups breaking. nothing against nikon, but that was a big problem they had. good thing they're re-designing them.)
a few reasons to buy vortex (these apply to stated models)
The warranty which i have already talked about. (does not matter what happens to the optics, they fix or replace for free).
100% waterproof and fogproof.
Every piece of glass has multiple coatings on all air-to-glass surfaces.
They are purged with argon gas which is higher quality than nitrogen. it gives them a better fogproof rating and also makes them more resistant to shock.
i know this was long, but i hope it helped.