Hi Brian, you are correct in your assessment. I personally put primary focus on DD as I believe risk control to be the key to the optimization of all other metrics. Of course, you can set risk at 0.1 for a signal with a 99% DD and have a 10% DD, but then your profit will only be 1/10 of expected and the signal will be more likely to blow up. I know that's an extreme example, but I'd rather use a low risk signal and dial up the risk setting knowing the signal is managed superbly than use a higher risk signal then dial down the risk setting. I personally don't use anything above 13% DD and nothing under 2 years in age, with some flexibility of course.
As someone else said, don't go just by the ranking, it can be misleading sometimes due to many factors (slippage, trading style and risk incompatibility, trading time, etc.) As an example, I actually paid $275 for 'Euro Specialist' and dropped it after a week when I first tried signals. It traded horribly and if you look at their results for the last 3-4 months, it is starkly different to what they were achieving before November 2016, so much so that I think anything before 11/2016 may have been faked.
That's another thing guys, always watch the trades, if things start to look out of whack, get the hell out ASAP, no matter what you've paid. No signals will work forever, market conditions are always changing and a good provider will adjust the signal's EA or trading style (if manual) to adapt to the new conditions. There are plenty of signals out there, there is absolutely no reason to be wedded to any of them.