If you need to make a lot of cuts, want good clean edges, or have to get precise angles and dimensions, a table saw designed for masonry units is the tool to buy. The kind of saw to buy depends on the kind of units you usually need to cut, the volume of work you plan to do, and the conditions you most often find on the jobsite. FULL-SIZE OR PORTABLE Most saw manufacturers produce two types of machines. Portable saws are smaller and lighter in weight (usually between 175 and 200 pounds). They typically are mounted on folding stands, and are fairly easy to load onto a truck and carry away at the end of the work day. Full-size saws are designed for higher production rates. Generally driven by a more powerful motor than a portable saw is, a full-size saw will cut the same material faster. ELECTRIC OR GASOLINE POWER The sole advantage of a gas-powered saw is mobility -- the ability to use it where electric service is unavailable. Electric saws deliver more consistent cutting power in use. They also tend to last longer than gas-powered machines, and that's reflected in longer manufacturer warranty periods. WET- OR DRY-CUTTING Choosing to cut wet or dry depends on the blade, not the saw. If you want to cut dry you need to use a blade made specifically for that purpose. Blades designed to be water-cooled must never be used dry. PRICE Portable saws list from about $1,200 to $1,600 for electric models; $2,000 to $2,400 for gasoline-powered machines. Full-size electric saws range between $2,700 and $3,100, and gas models between $2,700 and $3,400. Depending on the particular model, folding stands, foot-pedal controls, and other desirable options can add to the cost. Keep in mind, too, that blades for masonry saws are separate items. Blade prices vary widely depending on the size, construction, and quality of the blade.