XSPEC has been proven to be a scam coin. Just do a quick google search and you should find evidence that was previously posted here which shows that XSPEC devs were just doing it for the money. If you actually look closely at the project's github page it seems like it's an exact copy paste of some other blockchain and they even forgot to remove comments pertaining to the previous blockchain.
Pick ADA anyday over XSPEC scam coin.
Spectre is not a scam coin. Everything in regards to those accusations were based on JBG, the former lead developer. He and a few other members left and are going to start WISP, which they say will be a fork from Spectre, so everybody xspec will get wisp. Personally I don't think wisp will happen, and if it does it will probably just die of with time. JBG never delivered anything on xspec other than promises and almost killed the whole project.
Xspec now is however doing great. They have a transparent team and progress is being made. I won't buy any until they confirm a 3part audit being done by NCC Group and a whitepaper being released. If that looks good and they keep on track I will for sure buy some more.
Can't really say anything about ADA, as I don't know enough about that coin.