My initial disappointment (when running other than the supplied microsd) vanished when I used a fast microsd card in the Pi4. Splendid value and performance.
I now have it in a very early Pitop casing that provides screen, keyboard and touch pad to which Pi4 is only connected via HDMI and USB, with separated power supplies. I cannot find anywhere a short enough male to male HDMI to mini HDMI cable to suit and so the generous length of the starter kit’s HDMI cable is an annoyance in this special case.