Just stating facts here...
The previous video also includes the EC v2 air intake which is open box and more than likely their "go pedal" which gets you to WOT quicker. That alone even with out a tune or after market blow-off valve will make that noise. If you plan on doing only the tune or installing a closed box air intake (aFe) the noise is not as noticeable but you still here a little.
All these tunes are great as long as they're tested on a dyno and configured properly. It's not a "one size" fits all type of deal and each person will have their own tastes and preferences. I don't know which of the three tuning companies is better but i will explain below why i chose EC for tuning.
The big selling point on EC is that you can revert back to stock without calling anyone or doing anything remotely. Included in the tune is the configuration devices so you can easily swap back and forth from stock to tuned at will. The good thing about this is that i can remove the tune during winter months (based in Chicago) and slap it back on in the spring. I really don't need all that HP in snow

The second reason why i chose this is that EC is not only stopping on a single tune. Part of the package includes a more aggressive tune (should be released any day now) for those that really want to take their car to the next level. These two points helped me decided on EC over others. This doesn't mean it's the best but it was the best given my requirements.
The blow-off noise will certainly increase, the turbo is pushing @stock around 22-23psi so after the tune you're a lot higher in psi. Simple physics explains the additional noise. With that being said, open air CAI also produce a noticeable noise factor, i compare this to a home vacuum (not dyson lol) which is easily mistaken for a blow-off noise.
Hope this helps! I would recommend for anyone interested to head over to the giulia forums as all the tunes have been beaten to death long ago. Plenty of reviews and information to help you decide.