It’s very very different to the ID3. For sure the technology is behind the ID3 although I’m not convinced that’s a bad thing as the ID3 is all touch screens with not a button in sight. The I3 has less power but feels a lot more lively and urgent. The comparison I would say is that the ID3 is like a pretty standard Golf with nothing special in terms of performance or suspension/handling. The I3 feels much firmer and more hot hatch with a lot more performance available.
Practicality turns it the other way as the ID3 is very roomy and practical, the I3 is just about roomy enough but the door arrangement could be awkward.
Which is best, not sure yet but I do find the I3 a lot of fun where my conclusion on the ID3 was that it’s a bit boring but good.
Maybe an ID3 R version when it comes will be the sweet spot but not sure I can wait for that to arrive.
I’ve always quite liked the quirky i3, but it’s not very practical and my wife hates them for no good reason! A friend of mine has one and enjoys it a lot as a runaround.