Stealths offers virtual cards without KYC from their side, but some of the card providers may in exceptional cases ask for KYC from the client. However, it is one of the services that has been functioning for almost 1 year (at least as far as the forum is concerned) and no one (so far) has had a complaint about it.
Stealth sounds more convenient due to it being top uppable, if that is even a word.
I would not use it with Money I would not be comfortable with using anyway. I am still studying the two Cards you have mentioned and it seems like the International Master Card Stealths is providing does ask every time for a Phone Number and an Address too. I would be afraid it requires some sort of SMS validation for activating the Card.
And I do not even know what would be worse. SolCard asking for Know Your Customer or a Master Card provider doing it. I am inclined to believe the SolCard situation is worse, because if you only have one card that you have used for multiple purchases then your identity can more easily be found. Purchasing multiple Prepaid Master Cards seems less risky. That is considering you are not the only Prepaid user in the area and you are using the Card at different times in different locations.