external hard drive suggestions

[#1]

I Know there are stacks of reviews on the subject of external hard drives but is there any way of narrowing the final choice down.
Are 1TB drives just as reliable as 500/250 drives ?
Is it better to purchase one that has it's own external power supply ? (it would be attached on a permanent basis to the same desktop computer)
Is cost a factor ie the more you pay the more reliable the drive ?
Will any external hard drive made in the last few years work with windows 7 (PnP)
Thanks

[#2]

the best advice i can give you
is to buy one that is as silent in operation as you can possible get
outside hard drives well the one i bought certainly didnt  last  long before it started making all kinds of
noise while  i  saved downloads onto it  when i needed too

[#3]

I can recommend Freecom external drives. They are very quiet as they do not have a fan. Mine is 500Gb but if you search on Amazon you will find 1Tb and more. Look at this: http://www.amazon.co.uk/Freecom-31973-Hard-Drive-USB-2/dp/B002611YOM/ref=sr_1_1?ie=UTF8&s=electronic...

[#4]

I'm very happy with my Freecom. Extremely quiet, and in daily use for over four years now.

[#5]

If it is to be permanently connected to a PC, why not just install a bare disk drive internally?
It will be cheaper and (probably) quieter.
I've used a 750GB external drive for several years and two 1TB drives in separate PC's for about 18 months without problems.
But Terabyte drives haven't really been around long enough to be able to say that they have a short lifetime.
Cost doesn't appear to be much of a factor as the actual hard drive is made by only a few manufacturers.