To me, "reasonable" starts at about $250-300. It depends on the power you are convinced you need. I prefer 8 X , but can use 8.5 and 9 X with only a little more trouble. If possible, try before you buy!
I have owned Bushnell 8 X 42 Legends, Vortex Viper 8 X 42s, and Swift 7X 35s, and found them all perfectly adequate for general/birding/hunting use. I had used my Bushnells with great satisfaction, and my kids bought me a pair of Vortex 12 X ??? one Christmas. BEAUTIFUL binoculars, which I couldn't use more than 10 minutes without developing a headache. I paid a bit extra, and the Vortex rep replaced them with the viper 8 x 42s, which I have, and LOVE! My Granddaughter got the factory refurbished Swifts as a graduation present, and my son has the Bushnells.
There are two basic types of binos, the Roof Prism, and Porro prism. The Roofs are the most popular, probably because they resemble the High-$$$ Leica, Zeiss, and Swarovski glass. Used to be, the images were slightly out of "phase", but in the last 20 years, manufacturers of Binoculars have Phase coated their offerings, and great binoculars can be found in the $300-400 range Bushnell Legends, Nikon Monarchs, Leupold, Pentax, and all other major optic providers have good products for sale. I'll make a blanket statement here...AVOID the $39.95 "HUNGARIAN SECRET FORMULA" binoculars, and all other "bargain" offerings LIKE THE PLAGUE!!!
The Porro prism binos are cheaper to manufacture, may be lighter than Roof Prisms, and are generally of very high quality for an equal price.
Read the specifications carefully. The majors have both their lines of roof and porro prism binocs, and sometimes lower-priced lines are not as well coated. That helps light transmission and clarity. "Fully Coated", or "Fully multi-coated" is what you look for, because if they say Coated, or Multi-coated, generally, that means only the outer elements are coated, which is O.K., but not nearly as good as Fully multi-coated.
If you want good information, some sites are good, others not so much.
The the Cornell University Ornithology web site...they have done reviews on many binoculars, and are a good source of information. The Better View Desired site used to be a good source, but since the original owner sold it , I'm not sure. Eagle Optics, Christopher's and the Swift website have good information...at least they used to.
If you can afford the high-end Nikons, Zeiss, Leica(lust, covet!) GO for it!, but, if like most of us, Mid-range is all the budget will bear, I'm sure you will be pleased. I hope I have helped, and not told you how to build the whole bicycle, when all you wanted to know is how to change a tire!
Good Luck, it's an optics JUNGLE out there!
P.S. If I was just starting out , I would buy the Prostaffs, in the #2 post. And NOT under the seat of your truck! Take care of 'em, and they will last for years!
