The U.S. Food and Drug Administration (FDA) lists vacuum constriction devices (VCD) as safe, nonsurgical therapy for erectile dysfunction. Our study compared the responses of 30 male (10 novice and 20 regular) VCD users of seven commercially available systems (Mentor Response, Mentor-Touch, Mentor-Piston, Dacomed Catalyst, Mission VED, Osbon ErecAid, and Pos-T-Vac). Variables evaluated included simplicity of instruction, ease of use, cost, instructional value of videotape, company follow-up, presence of a pressure-limitation gauge, and length of warranty. The results from our study show (1) 100 percent reported an additional cost to be of minor importance in determining choice of device, (2) 80 percent of novice and 95 percent of regular users stated the instructional videotape was essential, (3) 95 percent of the participants desired a twenty-four-hour hot-line, (4) 40 percent of novice users but only 25 percent of regular users wanted personalized company follow-up, (5) 100 percent of novice users preferred single-handed devices, while regulars showed no preference. (6) Regular users scored Mentor Response, Osbon ErecAid, and Mentor-Piston highest regarding ease of use. While the vacuum constriction devices are conceptually similar, there are subtle operational distinctions between the different brands. The clinical urologist should be aware of these nuances.