Swap the tubes isn't that difficult. tube rolling is definetly not worth it here. But this is another time only my modest opinion.
If you have the possibility to test several devices, i would recommend it before burning your money!
Also imo the Amp is more important than the DAC. If it should be ifi, the Pro iCAN is the way to go. So you are more flexible with the DAC.
Just have a sober focus to the features of the Pro iDSD. Especially, if there is still the "amazing WiiM Player" after nearly a half decade...
Don't get me wrong, Thorsten Loesch is a genius. But yeah...all in all...decisions where made.
You shouldn't have problems at the end with a flagship device for a flagship price. That's it.
Cheers and enjoy music