Do a search on idle hammer or idle knock. The 1000's are prone to this due to the design of the clutch basket. There are a couple of people who will modify the basket for you and the sound is then gone forever.
Not sure of your motorcycling history but the for a first bike, I would tend to steer you towards the 650 as it will be a little more forgiving for a new rider. If you have been riding for years, get any size bike you like.
FYI - I have been riding for >20 years and have had several bikes. My 650 is now one of my absolute favorites. It will be my mistress for many years to come.
There are 10 types of people, those who know binary and those who don't.
What I ride now:
2013 Honda GoldWing (The Lady)
2014 V-strom 650 (The Mistress)
Previously: 07 Ultra Classic, 95 Softail, 80 gs450l