Have you messed with the sychroshift on your Ultegra Di2? Maybe a setting below will fix your problem?

Manual mode - Indicated by solid red/green LEDs. This is traditional, full-manual shifting.
Shift mode 1 (S1) - Indicated by both red and green LEDs flashing twice. The default S1 mode is semi-synchro: automatically shifts the rear derailleur when you shift the front derailleur.
Shift mode 2 (S2) - Red and green LEDs flash three times. By default this is full-synchro and this automatically shifts the front derailleur as you shift the rear derailleur.

Yes I have tried all 3 options. The rear will shift one cog at the time but fast so the chain can grip, this is the issue. With a mechanicanal group I just shift 3 cogs the same time and let the chain cross over all gears. This method would probably damage the gears during load but I don´t have any issues with this method for the last 7 years.

I hope all is well? I know the last time you mentioned you only had 150km on the bike and is too soon to tell how everything is. Is it safe to say that once you hit 1000km-3000km that this frame has been tested?

Everything is well here but the weather is cold, rainy and boring so I have started the Zwift season on my other bike instead. It only became 200km on it this season. I tried GP4000 S2 25mm and GP5000 TL 28mm on it. TL is a lot more heavy when it comes to steering, I think i want something lighter. They have less vibrations on rough tarmac on the other hand. I also need to do a bikefit on it to get most power out of my legs, it should have been done today but I had to cancel it since we have to much at work.
I´m not really happy with Di2 - On my other bike, I usually shift down 3 cogs rear and 1 up in front. It is possible to do the same thing on this but since the rear waits for each gear before shifting it will cause a very high cadence. Really useless to be honest. The good thing with 11-30 is that I don´t have to jump between big and small front in my area, but when I do - it´s annoying.

That's a good looking bike. Did you get those 50mm Roval wheels from them as well? What hub are you using? Looks like they are centerlock?

No they come from Sun-bike store on Aliexpress. Very nice and light with 1420 spokes, novatec 411/412 hubs. I didn't choose centerlock since my other bike have 6 bolt. But the disc's wasn't possible to use anyway so I bought XT 160mm disc instead of Ultegra. Just a few grams lighter.

Curious how it holds up over time.

 So youre paying for the design. Lets hope it holds up.

Same here. They offered 3 years warranty though.
I do value the design and paint. A black Dengfu with geometry like a Venge from 2015 would have saved around 200 USD.

F12 copy without custom paint may be a bit cheaper than mine too. DPD shipping is more expensive than EMS but I don't have any customs fee on it.

Post 6 is updated.

How does it ride?

I have pushed it a little bit but still need some fine tuning and bikefit. Cleats have been adjusted. My reference track over 40km was 1,3km/h faster with the same pulse. Wind conditions may be different and no watts compared.

My CX have really rapid steering and that´s why I want a road bike. However, this is very stable with 28mm so I think i will look for something else. I swapped to 25 again and will probably try again this afternoon. I´m looking on P Zero TLR or TLR SL to get something lighter. GP5000 TL vs GP4000 S2 with race tube is 55 grams heavier in system weight. I feel that in the hills and corners. But it feels good down and on the flats. I have 6kg front and back on the TL.

It´s hard to say something about frame stiffnes compared with my alu frame on the CX. It absorbs small road vibrations better.

It´s a comfortable and stable ride. Like I am on rails. The heavy tires does give a feeling to understeer. Top speed 57,6km/h so far but 52/11 is capable to a lot more with 100 in cadence.

Weight without bar tape and chain was 7,4kg GP4000. With chain, bar tape and GP5000 is 8,4kg. Lighter chain and tyres would be nice but after all, it is a big 595 bike.

Ultegra Di2 -  I think it shifts a bit slow on the rear when it does the sync shift from big to small ring in front. It´s like it´s waiting some milliseconds before it shifts between the cogs on the rear so I will spin up a lot first and then stabilize on correct cadence. A wire was actually much better her. I dropped to small ring and push the right lever 3 kogs the same time.

Pictures added to post 3,4 and 5.

Yeah, I've like the idea that once you have the "brand" (Pinarello in that case) they can put the quality at second place, but again, that's just my idea. And I hope I'm wrong considering that I ordered the sl7 copy.
So untile the parcel is not in my country I basically can't track it I assume

It was possible to trace it when it arrived to europe but no update from China to Belgium. I did look on the SL7 too but they didn´t do 61cm. I think 58cm was just a little bit small.