I like Rootstock. I don't like Stacks. When Stacks describes themselves as "the smart-contract layer of Bitcoin" I think Rootstock, with their lack of a scamming altcoin like STX is far more deserving of that. Of course, Bitcoiners define layer twos as having the asset of layer one and being able to return to the layer one trustlessly. Rootstock, like Liquid, as a federated sidechain, pegging out is not trustless. This leaves only lightning and statechains as the two only real functioning layer twos, as Bitcoiners define it. Not sure why Ethereum counts an altcoin on Ethereum as scaling Ethereum.