I find bus drivers consistently give me worse overtakes than HGV drivers.
Here in Manchester, they vary.
The ones to watch out for used to be Finglands and "Magic Bus", with the other companies, mostly, being ok. (Finglands were mostly impatient, Magic Bus were just nasty, and I saw several incidents of them hassling cyclists by tailgating, punishment passing, &c) Recent changes to the road layout (e.g. the addition of traffic islands at some points that prevent their old trick of encroaching on the bike lane well ahead of an upcoming stop) have mitigated some of their behaviour, and Finglands have been taken over by another company recently.
Outside the city, the school services on old "Dublin Bus" vehicles (quite a distinctive blue and yellow livery) are driven appallingly, and I avoid those whenever I can. (Timing my commute to arrive before, or after they pass along problematic sections of my route). On one particularly memorable occasion, one driver attempted a pass by traffic islands, then tailgated me leaning on his horn when he couldn't pass, then punishment passed me, all to reach a red light one or two seconds before me.
On the upside, the 37 service, which I see a lot, is superbly driven, and I couldn't ask for a better example to other drivers than the one set by the drivers of these buses.