I've got a sheet of glass on mine. It's easy to clean - anything that sets up on it (glue, paint, masking tape etc) scrapes off easily with a single edged razor blade, spilled paint or other liquids don't soak in and wipe up easily. It's also a great cutting surface (cutting does damage the surface, but it takes about five years before the surface becomes unusable - then you just flip it over.
I've use a lot of different kinds of glass over the years (for a while I even had a co-pilots side window out of a KC-135 on the desk - a couple of feet wide, about 4 feet long and 3 inches thick - weighed a ton). Currently I'm using a piece of glass that came from a desk top - it's about 5/16" thick and really resists breakage and damage.
If you do go with glass (I highly recommend it), don't use standard window pane glass - it breaks very easily and cuts better than a razor when it does. The thicker the glass the better and you want to make sure the edges have been rounded (guess how I found out about that). If you should scrounge or salvage a piece of glass you think will work for you (that's how I've gotten all my glass work surfaces), don't try to cut it yourself. A glass shop will cut it to size and round the edges for you for a few bucks. (which is cheaper than any medical bills and pain you might get if you try to do it yourself)