I've drooled over those as well.
Unfortunately, I would not install the ones 72VETTE454 is looking at... sorry... I don't like MR lamps in this type of application. They are meant more for accent lighting (decorative) rather than functional illumination (lighting a work space). A PAR lamp does a better job at the latter. Even more so for those cheap LED fixtures - which are
really meant for accent lighting. IMHO, those would be a big waste of time and money.
Back when I was looking into this, I found these:
http://www.elights.com/15295az.html
I agree that shadows could be an issue... not to mention glare (which has always been an issue for MR lamps)... for the above fixture, I would use a CFL flood lamp with an opaque coating/diffuser.
I have big hopes and plans for LED lighting... but at this time, they're just not ready.