Doesn't look any slower to me.

That video shows....nothing?

we don´t talk about seconds in difference so hard to se that you should be able to se the difference

If we could reach a consensus before I have to press buy, that would be great.

If you haven't ridden D/A Di2, you'll never know the difference. Ultegra still will never miss a shift.

i have both, in real world use, not any difference, you change gear, it happens..simple!

but as far as quality is concerned..obviously the DA is better, rear mech is smaller. YES the new wiring harness is ver good, but both of mine are internal so makes no odds really.

weight, you wouldn't notice a difference on the bikes.

one thing for certain is the DA is faster that the ultegra, not by miles and hardly noticeable, but faster all the same..but what do you expect! if they released the ultegra and it was faster and better than DA then they would be stuck with loads of units they couldn't sell!

if i was in your shoes, and had the cash, id go DA, you already have the callipers and chain set (I presume?) so only the elecs would need upgrading. mixing DA and ULT just looks weird lol.

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"Heroes do not die, they re-load"

does the ultegra wiring harness work with the dura ace di2 components?

The 9070 series Dura Ace Di2 uses the same E-Tube wire system as the 6770 series Ultegra Di2. So if you want to upgrade your Ultegra Di2 components to new DA Di2, you can leave the wires in the frame. The old DA Di2 uses a different cable system and is not compatible with Ultegra or the new DA.

I must say that I didn't noticed any difference in front shifting speed between DA Di2 and U Di2, but could be me.

Comparing Ultegra and Dura-ace Di2.. Hey, if you have the money. Go for DA. Although I rather spend some more money on nice wheels and tubs instead.

Just want to add: When people walk into the shop they often make a comparison between mechanical 7900 Dura-ace and Ultegra Di2, as it's basically the same price. I cant believe how many people choose the mechanical DA. The Di2 groups, both of them, are so much better in reliability and performance.

There is updated firmware for all of the ultegra di2 components. I could be wrong, but when I updated them it seemed that shifting was a bit smoother and faster.

There are a LOT of people that simply do not like electronic - I'm one of them. I don't like the way it shifts, especially with winter gloves. I don't have any reliability issues with my mechanical, once the cables have stretched it is good for thousands of km.

For CX or XC I can see the reliability concerns due to mud.

yep, the latest firmware seems to speed up the shifting

What do I need to update te firm ware

You need the Shimano E tube system checker SM-PCE1

http://techdocs.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/SM/EV-SM-PCE1-3138_v1_m56577569830781074.pdf