I've tested the two best solvers many times and the results were consistent.
I've asked corwin42 to explain his solution which looks pretty complicated.
The fastest solver and the puzzles are attached.
I'm currently short on time (my daughter is celebrating her birthday today. ) and I will write a longer comment this evening.
I even will give a small description of how I did it in the next days.
I would love to have a look at the other solutions, too. I think they are all very good. 4ms to the second place is not really that much and I think that I had the luck on my side.
Out of curiousity: what device did you test them on?
FWIW, on a Toshiba Thrive, it ran in 12ms; on an Archos 70, 22ms. These were the times of the first runs on each device. On the TT, subsequent runs were 7ms, 6ms, and 5ms while on the A70, after a half-dozen runs, it got to 12ms, but actually fluctuated up and down. I think that I've seen such changing run times discussed on here before, but I don't remember what causes them.