These strobes work very, very well. There's no way other drivers can't see you coming.
I just finished the install. I recommend getting a switch panel, I got the Galls one. I had plenty of spare wire (installing on a sedan) but didn't have enough connectors. I am missing a female connector, it may have been lost somewhere during the install, but I would think that for the amount of money you're paying, they should throw in a little extra plastic pieces. Hopefully Radio Shack will have some...
The instructions are good, except if you're a novice consider getting this professionally installed. I spent about 8 hours total installing in my sedan. Feel free to split it up though, I did the cutouts on the lights (1 holes) first with a Dremel one day, then installed the box, then installed the wiring (the longest part), and then installed the switch panel.
Also, I chose to put voltage on the optional flash pattern selector circuit rather than the hi/lo selector circuit.