My broadband provider is BT so it's a pukka Openreach engineer. I'm not risking more cowboys, I'd rather pay for someone who knows what they're doing and have done with it.
Lets hope you don't get a Kelly's or MJ Quinn Subcontractor, I have always bad work done when its been a Kelly's engineer, might of had the odd MJ Quinn engineer, don't recall if I had any issues with their work.
If you are with BT for your broadband, I would of asked BT if they could send out a Boost Engineer, they will disconnect your whole master socket and BT80 (if you have one) and re-do them, they will also try and get the best possible stable speed for your line with and without the internal extensions if any.
TBH I cannot fault the BT Boost Engineer that we got, very polite and chatty and wasn't in a rush like Kelly's or MJ Quinn engineers always have been.