yes and yes :) i think it might be a good idea to find a plumber you trust, not only for the installation, but for repairs if necessary. i really did not know for sure what i wanted or what brand to buy until i consulted my plumber.
i was lucky to have someone already before my kitchen project.
the heavier the grade, the better the sink. it just depends on what size you want and how it will be used. they do scratch. i thought it would not happen to moi :) but it did! once the crisis of the first scratch is over, then you will be fine :) as for the faucet? it's personal taste and quality. We got an Elkay sink and a Delta Faucet.

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