You’ll get good coffee after the first grind. But it will get better over the next few kilos. So it comes down to how badly you want to get to optimal espresso.
With most new electric grinders I put 2kg through right away. Even with the benchtop Livi hand grinder I put 2kg through but holy molly it was hard yakker. With a handheld hand grinder it’s harder again so I tend to grind 20g (and bin it) and just accept that the espresso will be good enough from then on, but a little sub optimal to begin with.
You’ll also get more static spray at the start and you’ll be adjusting the dial a bit more. But even with the most difficult grinders, that almost always settles down at the 2kg point.