does anyone know of any solution similar to 12speed garage door opener?
I expected to have seen something in Ali by now, but no sign... I find the product really well thought, but being outside the US and with exchange rates the 'original' option is not feasible

I agree with this but the price difference is massive. I have been using generic stuff for ages and works well. I've not removed it from any frames to which it is applied but I cut lengths of tape onto parchment paper then used a scalpel to cut the pieces nicely. Came out okay, definitely not like an Invisiframe kit though.

Sounds fun, got any pics of those?

And yeah, I totally get you. I'm just a sucker for colors. Resale value is a good point as well but it isn't a high priority for me.

The issue arises with the C ring. It sits very good on the bearing but there is movement between the inside of the C ring and the steerer tube of the fork. I did not tighten everything down since I did not cut the fork. My presumption is that this interface C ring/steerer tube is the source of the headset play everyone is experiencing. Is it normal for this interface to be so slack or should this be snug? Steerer tube measures 28.6mm as it should but the inside of the C ring is close to 29mm (28.. I think of shimming this to eliminate the play. This is my first integrated headset that I have been working on.

No, I don't, and I have been looking at other options. That said, I'm a bit confused about compatibility between integrated headsets.
I'm also considering a traditional handlebar and routing the cables under the stem into the headset.

Tempting and not tempting! The ER9 is slightly cheaper at $347 USD and they are adding discount bonuses bringing the total right under $360 USD with tax+shipping. Personally the ER9 has been awesome for me, but it's hard not to ignore issues other users have been facing.