You can get 3-3/4" line voltage cans with MR16 like bulbs from Halo lighting. No buzzing, same depth as low voltage (unless you are getting super small WAC lights or something)

All lamps with filaments can buzz when controlled by solid state dimmers. Low voltage fixtures with integral transformers can sometimes contribute to that effect. The solution is to use the better quality 3-wire solid state dimmers, the better quality fixtures that have better transformers, and keep the number of fixtures well below the max. capacity of the dimmer.

The only reason I can think of to use surface lighting is to avoid paying for the more expensive recessed fixtures. The difference in lighting is obviously dramatic.

What brand are you considering and what ceiling depth is available?

Whatever you use, always buy lamps/bulbs at an electrical supply store rather than at a grocery store, lumberyard or home center and ask for the best quality they sell.

Thanks for the info. The ceiling depth is 7 1/4 inches. I think the electrician is installing Elco can housings. I'll ask him about the dimmers.

You still have options for lower priced "line voltage" cans, and it all depends on your requirements. If you are using insulation in these ceilings where they are to be installed, then your choice is 4" line voltage IC/airtight only which will come in at 5 1/2" deep. If you are not using insulation... then you can use 6" shallow cans for Non-IC installation at the same depth. I would not use low voltage for general recessed ceiling lighting. Low voltage is great for spot, art, and accent lighting where the negative benefits of producing heat and being very white/blinding is not a problem since it's directed at an object.
JMHO

I would not use low voltage for general recessed ceiling lighting. Low voltage is great for spot, art, and accent lighting where the negative benefits of producing heat and being very white/blinding is not a problem since it's directed at an object.

I asked this once before, but it seems pertinent in light of this comment. When and more importantly why should you use low voltage instead of line voltage recessed lighting?

"When" and "why" would be for the added spectral range and beam projection flexibility that would not be available with conventional line voltage incandescents.
General area lighting of rooms dictates broad beam width incandescent line voltage especially when one is using recessed downlighting. Line voltage incandescents produce a pleasing skin tone.
When object, accent, art, comes into play...the low voltage halogens for example, give a much more adjustable beam projection and color correctness. Depending on the wattage and kelvin scale bulb, one can get the exact beam pattern from a set distance, to highlight their art w/o highlighting the bad spackle job just inches away.

We just turned on power, and I'm happy to report that my Juno 4" low-voltage cans in my new kitchen do NOT buzz at all. I was getting worried after reading the posts on the forums as well. The light is pretty focused though, but the MR16 flood bulbs are just sitting in the housing since I changed my mind and ordered haze trims. Can't wait to see what it looks like when they are complete!