Nice to get some serious feedback. I also urge folks to check out Pete R.'s more detailed notes, although he doesn't mention what spike-driving chants he uses while he installs them. With some banjos I wouldn't worry about being so careful as Pete but if you have an antique one with an ebony fingerboard, you really want to pre-drill to avoid unintended chipping. I also agree that if possible the spike should be emplaced so that the 5th-string is not bent out of line, and I would even recommend a slightly higher bridge if the "site" was marginal for buzzing.

There are other more elaborate 5th-string capos but they generally strike me as unsightly.

Maybe what I'll do is donate a box of 3000 to the Mudcat Auction and the Mudcat Syndicate could get filthy rich processing 300 or so orders.