Those that have them love them, and those that don’t are often out of luck since it appears they are no longer made. However this page still shows them as a product (with pictures showing Cole drill setups). There were a number of accessories available, and the pamphlet shows the many uses. They do show up on eBay from time to time, though the one listed now is in relatively poor condition. The drills are chucked in a 1/2″ hole with a set screw, so Silver and Deming bits are often used (although some people will mount a drill chuck).
Special thanks to Rob Skinner and Kelley Garcia of the Rusty Iron Workshop in California for use of this great photo. Check out their antique engines, machinery, and tractors here.