First you need to figure out how much light is needed.

Assuming ~ 35 lumens per sq ft and a 10 x 12 area the total light required is 4200 lumens.

If the cans produce 600 lumens each, you would need 7. The underlying premise is that the cans will be used to provide all the light needed.

The cans should be spread out to provide lighting around the counter tops. This works out to approx 26" to 32" from the wall, depending on the presence/ absence of upper cabinets, depth of the cabinets + crown molding, location of joists and other obstructions (e.g. - HVAC, plumbing, ...) in the ceiling

Traditional can lighting (incandescent, CFL) tends to produce light cones / spot light effects due to the use of PAR lights and the geometry of the can.

Anytime a light bulb is put into an enclosure, some amount of light will not be usable. So a 800 lumen A lamp bulb will not seem as bright.

LED lamps such as the Cree LR6/ CR6 and the Sylvania RT6 perform much better as the light emitting diodes are all facing forward and not very deeply recessed. Some would complain that the LR6 has excessive light spillage as the led diodes are the least recessed.

6" can enclosures are the most common and use standard 120V. The traditional can comes in 3 parts - the enclosure, bulb and trim.

If you use the Cree or Sylvania LED lamps, you can omit the trim as it is already fitted to the lamp (unless you must really have a custom trim piece).

The type of lighting you put in may be governed by local energy efficiency ordinances (eg. Title 24 in California)

Compact fluorescent (CF) Cans with an integrated ballast will cost more than the standard can. The total package could be less cost effective than CR6/ RT6 + title 24 rated can. Home Depot is selling Commercial Electric LED modules under $40 today.

If dimming is a requirement, most CF cans would be ruled out.

Although the CR6 and LR6 modules are dimmable using incandescent dimmers, not all dimmers perform equally well.

HTH