Xindak DAC 5 Mod Burson OP Amp Upgrade

Any experiences with repalcing tho op amps BB2604 to the Burson Opamp 101 in the Xindak dac 5?
If you can read French, there is a very detailed description in the following link:

Apparently, it's very worthy.
Has anybody attempted to run the dac 5 without the tube. I don't use the tube output. Can the unit be damage, if I ran it in this configuration.