I've been using Startron for about 8 years now. 6 of those years was in an unheated garage and it would regularly get down into the twenties in the winter. Before that I used Marine Stabil.
I have had no issues with Startron and the bikes run great and start right up after sitting for a while. I use it on a regular basis as it is suppose keep things from gumming up.
They now make a small 1 ounce bottle which I keep on the bikes so when I am out I can add it.
"If it ain't broke take it apart and make it work better"