Can't try the current one ("request an invite") but I used the experimental version you mention and it always had a pretty poor performance for me, even on bran

Can't try the current one ("request an invite") but I used the experimental version you mention and it always had a pretty poor performance for me, even on brand new hardware which handles other webGL demos and my own webGL projects pretty well. So I guess what this shows is that webGL is still pretty hardware and implementation dependent.