After reading much online I've decided to by a 10x50 porro prism Binoculars. The one I have in mind http://www.letsbuy.com/celestron-upclose-10x50-p-34652 has BK7 prisms. The one I would like to buy is this: Olympus 10x50 DPS I but it is never available and a tad bit more expensive. Is buying binoculars or telescopes online a bad thing as I've read you need to inspect them carefully before buying? Also will the prism difference (BK7 vs BAK4) make much of a difference for the 10x50 range?
Buying directly from the shop ensures you will get collimated binocular instead of buying it online. But there are some companies such as Garret Opticals from US. They ship with great care & the binocular comes with excellent collimation. I ordered their binocular Gemini 15x70 it came with excellent collimation. So if you are in US then you can order from them.
Yea the difference between the optical clarity depends on the type of prism used.
It is ok to buy NEW telescopes and binocs from reputable dealers online. I wouldn't buy any used optics online. I bought my 11" scope on the web . . . otherwise I would have had to drive about a 600 miles to get one at a store.