Personally, I have never had Guineas, but have friends that have had them.
Noise: Many people don't like the little 'chatterboxes'. If they are not kept near the house, it shouldn't be a problem. They 'talk' about anything that happens within their territory. They will alert you when the mailman (or anybody else) shows up. If you dig up a flower plant in their yard, when you let them out in the morning, they will gather around the hole in the ground and 'discuss' the change in
their yard - they are very observant of any change - nothing slips by them without their notice. That probably has a lot to do with their survival instincts.
Training: Yes. If you get adults, or even grown chicks, their instincts will tell them to go find home. It has been reported that they need to be confined in their coop for about 6 weeks before they will accept it as their home. Even if you start with young keets inside your house, they still need this time period to engrave in their minds that
this is home.
We have a few threads here about Guineas:
https://permies.com/forums/posts/list/26828#210725
https://permies.com/forums/posts/list/30928#240239
https://permies.com/forums/posts/list/40/12290#159471
And one specific to hawks:
https://permies.com/forums/posts/list/33410#261149
I honestly believe that each species has its own strengths and weaknesses. By combing a mixed flock on the pasture, you gain each of those strengths. Beware however that turkeys are prone to Blackhead disease, which is passed from fecal worms which are common in many chickens. It is generally recommended to not combine turkeys and chickens because of this disease. Many have reported mixing the two without problems - but probably more have reported mixing them with fatal results.
If you do decide to go with Guineas, I highly recommend that you get
Gardening With Guineas by Jeannette S. Furgeson . If you buy it directly from her, not will she actually make something from it, but will even sign the book (if you check that box).