Lighting grade LEDs get hot too. You have 3 watts dissipating in a tiny silicon die. It's not a whole lot of light output though. LEDs are good for very focused spot lighting. How focused do you want the beam?
30 degree is considered spot but I think these are 60 degree more like a flood.
It doesn't need to be real focused, just for washing dishes and more for accent.
I doubt 3 Watts in this fixture is going to even be close to a 20W MR11 halogen bulb... the above cabinet is 36" wide so there is alot of air space. If I have a 12V system up there I can easily add a temperature regulated fan also. But I doubt I would need it.
I am looking for a total lumens close to a 40W incandescent, around 600 Lumens or so. (so probably need 3)