I'd say you've done your test tour of duty.Second time in the last 3 months I managed to get a screw in the tire (see picture). The tire started to deflate fairly quickly. Stopped, reinflated tire. Couldn't visually find the screw. Air still going down. Stopped again, found the screw, removed it and pumped to about 40 psi. Drove for about 10 km., stopped, let some air out to correct pressure and then drove on. So far so good with pressure holding. The trick seems to be to remove the object put air in, drive a while and that allows the goo in the tire to seal it up. Works like a charm though I don't want to keep testing this technology!