In my opinion, you should avoid them all.
It's relatively easy (given plenty of knowledge, understanding, judgment and due diligence!) to identify a signal service that has had a good few months of profit, but (and here's the point) it won't be the same one that's still making profits in a couple of months' time, and there are reasons for that, which aren't trivially easy for the uninitiated to understand.
There are thousands of signal services "out there" (and unfortunately quite a few of them "in here" as well!), and at any one time, out of those thousands, it follows that there will be a small number who happen, simply by the laws of chance, to have had a run of a few good months.
There's also a process at work which statisticians call "selection bias", which predicates that those few are usually the ones you see advertising and promoting and being recommended most prominently.
Unfortunately, the fact that they happen just to have a few good months has very little (or "no") bearing at all on their chances of having a good few months again when you subscribe, because they had it by luck and "because someone has to", not by skill. They're successful marketers, not successful traders.
That's the "hidden reason" why it's so very, very common to join a successful service and for it all to turn sour as soon as you start paying for it.
And welcome to the forum!