I saw a bunch of great systems advertised online, but I think a ton of them got whipsawed during the market craziness of the last 6 months, so their performance record right now probably does not appear so great.
The best one I have seen was one I first traded a few years ago. I traded it for around 3 months and had to top up my margin twice in this period. I will dig out the real results (if I still have them) because they are always good for a laugh. But from what I remember I was currently about to experience my 14th loss in a row and getting close to having to top up my margin for the third time. Looked fantastic in back testing