I think the whole heirloom idea is great.
However, I personally wouldn't go for a 16610 - most common Rolex there is.
A nice 1680, if you want a date, otherwise a 5513.
I know I would be happier to get something a little more unique than the "entry level" luxury watch.
Hell, I say everyone wearing a Planet Ocean has put more thought into his choice of watch then everyone wearing a 16610.
In Manhattan, every 15th man on the street is wearing that sub.