Does this count as Modern?
Do not let all the gushing about the Streamliner make your decision for you on whether to get one.
Ask yourself this simple question. Do I like the sound of an all Tube head or do I prefer the snap quickness of a SS head.
Do you like your tone squeaky clean or do you like some warmth----overdrive.
The Streamliner will get quite bright if you want it to and is a bit too much bright overdriven (you have to roll back the highs when playing dirty). It will do squeky clean as well but with that tubyness built in.
It will sound great with a modern bass if your preference is that warm gooey tube amp type tone. If your preference is that quick snappy SS type tone the Streamliner is not it.
The Shuttle 9.0 will do a little grit and is closer to that quick SS tone with a smidgen of warmth added in for good measure.
There are so many choices it is a good time to be a Bass Player.