Rendering A product using vray in 3Ds MAX: What is best lights setting?

In Product Rendering we need to setup a studio. In this studio you can then render every product even Crystal, Glass or Metal. So, the studio must have enough lights to enhance the product. Here is a tutorial that can help you for the product studio render setting. 

http://cgi.tutsplus.com/tutorials/studio-rendering-with-3ds-max-and-vray--cg-1801

Vray settings can be quite complicated to the novice, but very rewarding once learned. Every scene can have different settings, as everything is connected (the lights, materials, sampler...etc). You just need to tinker until you find the best settings on all fronts. When it comes to crystal and glass, then the question would be how glossy are they? Cause once they're not100% glossy, then render times can escalate drastically if the settings aren't optimized. Learning the DMC sampler is the best way to go in my opinion, and here is the best tutorial I have come across in my experience: http://interstation3d.com/tutorials/vray_dmc_sampler/demistyfing_dmc.html .

Where3d product visualization is concerned, one of the most important techniques for achieving realistic high quality images, is your ability to create studio renders. In this Render studio you can render every product even Crystal, Glass or Metal. VRay has many features including the ability to physically accurate full global illumination, advanced material shaders and enhancements for speeding up rendering time.

Using V-Ray light sources (VRAYLIGHTS) is the best choice when working with

V-Ray. These light sources behave with physical correctness. Unlike standard

light sources, the light is emitted by a three-dimensional source, not by one

point. VRay Lights require shorter rendering times, have integrated falloff as

the standard, and always produce a realistic-looking area shadow.

Here is some links that can make help for the product studio render and lighting setting.

http://cgi.tutsplus.com/tutorials/studio-rendering-with-3ds-max-and-vray--cg-1801

http://help.chaosgroup.com/vray/help/150SP1/light_params.htm

http://booksite.elsevier.com/samplechapters//02~Chapter_1.pdf

light settings can be given according to depth of the product to be rendered and its special feature, more than light setting rendering tools and proper texturing plays major role in rendering good product image

It depends on the model and the envoirment. You can use daylight or indoore light. 

Well it depends on your model and texture.

They said enough, nothing more unless it's not a back shot

it will be totally different 

The best light / rendering settings is the one that gives best balance of look and rendering time. The scene, lights and shaders dictates the settings on different levels of rendering. And if rendering requires passes, that is additional material to talk about.