Has Anyone tried the new JJ KT66 tubes

I would like to know how their performance if anyone has tried the new JJ KT 66 tubes
no I haven't, but I do have NOS GE KT66 in my primaluna prologue 2 that surpass any current production KT 88 or EL 34 tubes I've heard. These are a rare find, right off the shelf in some back water hi fi store. The balance and tone are the best. I would think the JJ KT 66 tubes are pretty fine.
are these drop in replacements for the el34?