As mentioned above, it's all about the optics, and you sure won't get anything quality at Harbor Freight. If the lens and prism's aren't correctly aligned, all you're going to get is a headache and a field of focus that is not flat.
Additionally, unless you have a very steady hand (maybe a tripod), x10 is useless, which is why the mariners standard is 7x50, 10x are simply too hard to steady. 7x50 have good magnification, and a bright lens but easy to hold. Likewise, stay away from 7x35's. They are just OK for daytime use, but if you're looking for wildlife, etc. while camping in low light and at night, then 7x50 is the one.
Look at WestMarine.. They used to have WestMarine branded Bosch & Loumb waterproofed and gas filled binocs With compass for $250. The OEM was twice that for the exact same equipment
I probably keep about 8 or 10 pair of binoculars around, some in the truck camper, some in the 5th wheel, a few in the house, truck, etc. They run the gamut of prices. The real cheap ones, less than $100, are no name foreign made ones I have bought here and there. Great for my young grandsons to beat around with on trips.
Then I have several in the lower mid range of prices, $100 to $300 each. These are mostly Bushnell brand, one of the favorites of all of us is a 7-15 zoom x25. Good for bright light only. Bushnell has done free repairs for me, years after the warranty has expired. I have sent a couple of pair in that had been abused badly, mainly in my power boats, that had fogged up inside. Enclosed the $10 repair exam cost and then is a few weeks back would come my binoculars, with a note that they had received a "courtesy cleaning and re-gassing. No charge other than the initial $10.
In the upper middle range $500 to $1,000, I am very partial to Leupold brand binoculars and rifle scopes. My favorite of all my binoculars, are a set of 10 x 42 waterproof ones, Gold Ring model as I remember. I bought them to use on my sailboat running around in the Caribbean. Some people feel 10 power are difficult to use and hold steady, but I have never found this to be true with high quality optics such as the Leupold's have in their upper price range. I paid just under $1,000 for the 10 x 42 pair I have and have had for about 20 years or so now. For spotting channel markers, checking out fast approaching boats, checking out the crew members on boats sailing out of Martinique or other French influenced islands, they were the best. I also carried a spotting scope. With go fast boats out on the open ocean, determining "who" they were, would give me a few extra minutes to decide how to welcome them. Be they Bahamian Defense Force boats, Cuban Navy boats or drug runners and/or pirates. You never wanted to greet the BDF boats or the Cuban Navy with an assault rifle in your hands. But that was what the others understood the best, and always chose to look for someone else.
So it really depends on what I am going to do with binoculars as to what I buy.
Formerly of Colorado and Alaska
2011 Chevy 3500 DRW Dmax CC 4X4- Rockwood 8281 SS 5th Whl & 2008 Lance 845 TC www.pajbcooper.com web site
Alaska-Colorado and other Trips posted
"Without challenge, adventure is impossible".
Don't worry about wearing glasses.
Once you adjust the binoculars to your eyesight without glasses the image will be crystal clear.
Get a pair with extra wide angle or whatever they call it. They let in more light and give you a clear view in dim light.
If you do any hiking with binoculars weight and size start to enter into the equation. Naturally there are those tiny compact binoculars but the field of view and light become a problem with most of them and they are generally lousy for bird watching. The binoculars we previously had, 10x50 Bushnell porro prisms were just too heavy and bulky for my wife to enjoy hiking with despite have a shoulder harness strap. That's something to think about.
2011 Great West Van Legend Sprinter B Camper Van
Visited states in an RV
I am going to suggest a different route. Buy a pair or two of relatively cheap binoculars, say at $75.00 to $100.00 a piece so you don't have to share. If you are in to either photography or animal watching, eventually you are going to want a spotting scope. $300 will buy an adequate scope, $1500 a great scope and if you are really into it, $3000+ top of the line. The difference in a scope vs binoculars is amazing. Most serious animal watchers I know never pull their binoculars out of the case.
Good inexpensive binoculars I have owned are from Orion. Whatever you get be sure they have multi-coated lenses and are anti-fog and waterproof. Then you can use them anywhere without a second thought and they can be stowed in a small wall mounted rack and not have to be inside a case all the time.
8x or less are much easier to use hand held. Greater magnification and you will want to mount them on a tripod. There are optically stabilized versions and though expensive they do work to make it possible to view with greater magnification.
The second number is important as it relates primarily to the amount of light that gets to your eyes. It is a rough indicator of the field of view as well. I prefer a 8x x 50 binocular as it provides good magnification but is easily used hand held and it lets in a lot of light. I have used mine for greatly improved vision at night and are particularly helpful for sailing into harbors where you want to be sure you have correctly identified the entrance lights.
You will find that the field of view can vary by more than 50% and the wider the field of view the easier it is to quickly see something. For whale watching for example a 8x50 is going to be more useful than a 7x35, though the 7x35 will be smaller and lighter.
B&H Photo Video is a good place to shop for binoculars as they have great prices, a great selection, and lots of user reviews that are helpful.
If your planned use is birding and similar activities there are forums that have reviews of different binoculars and these can help though often they are for the top end ones that are expensive. As the only piece of equipment a birder is ever going to need they are not going to have the same perspective.