Yes, the ECC801 is basically a 12AT7. It is primarily designed for long life, not for lower distortion. Two things that are audible are:
1) it withstands a lot of vibration, so can be expected to be relatively free of microphonics, and
2) the cathode won't develop an interface resistance, making it likely to be quieter and maintain its performance as it ages. This is often associated with tubes that are "better sounding," so there may be some magic beyond the known technical specs.
