As a website designer I am looking into upgrading my 2x Benq G2420HD monitors into something better with much more accurate colours. Lately I have been looking at the Dell IPS displays as they look pretty nice.

The only challenge I am faced with which is preventing me from buying them is: even if I have these amazing monitors that will allow me to view my websites in their most accurate colours - how am I so sure that the rest of the web will be viewing my websites the same way?

Is there a program or perhaps a website that will allow me emulate what it would look like if I viewed my websites from different monitor model numbers? Or perhaps this is where the term "web safe colours" comes into play and I should never stray away from them if possible? For example, I will see white text on green background at 12px font size just fine on a Mac monitor, but on a $150 LCD monitor running Windows 7 it will show up washed out and hard to read. It's a bit of a headache trying to guess how the audience will be seeing the website and if they can actually see the light grey on white as it is intended. (These forums are perhaps a good example of light grey and white - for me right now on the Benq's the grey is hard to pick out unless I tilt my head down close to my keyboard and look up at my monitors.)

Any tips and or advise is greatly appreciated.
Thanks!