Well... the Speedball Crack looks similar to the Woo Audio 3, or 3+ - which is superb amp (uses the same tubes), and which costs only "a few dollars more."
If it were me... I'd be opting for the WA3.
And... while I liked the WA3 a lot... the Whiplash Audio Millett MiniMax sounds virtually as good - depending upon what tubes and phones are used.
So... for my money... I'd be getting one of these - much easier and only "a few dollars more."