My wife and I have a kitchen with an island, and as usual, with an island the light ended up being behind you when you're working at the island itself.

I'd like to add some lights, but my wife has insisted that it be flush (recessed) with the ceiling. Now, this is fine with me, but the problem is that the place where the lights would go is right where the ceiling beams are. So, if I went with a standard in ceiling, recessed light, they would end up 'off center' from the center line of the island. This bothers me.

What I have found is a 'puck' light made for cabinet and ceiling lighting. This can go right up against the beams, and appear to be recessed lighting - only about a half inch would protrude.
You can see them here: http://www.lowes.com/pd_366540-53027-EC5055WH_0__?productId=3531602&Ntt=puck+light

My problem is that these are only 20 watts each. If I put up all 5 of these, is this going to be enough light? how much light do I need?