How do I decide on which components are good or better than others ? How do I decide the best buys.
First and Foremost we can google the product we wish to buy and check it's reviews or what others experience about the component you wish to buy. You may also post your queries on any of technical forums and get replies from other users.
Second You can check this link .. http://bwindia.net/content/check-benchmarks-various-pc-components and compare benchmarks or various components on how they tested on standard conditions.
Next You can ask your techie friends who can give you advise and tips suitable for your needs.
Then, You may ask us, but our knowledge is limited since we don't use or test most of the products we sell, but we have valuable feedback which sometimes can help you.