It will all depend on your driver how the experience will be. Given our rating...we hit it well with our driver. Unfortunately we didn't catch his name. (Slender build, Guessing on 50s or 60s w/glasses, white hair) Very professional and caring to passengers. He knew Boston and the history.
Our Tour guide wanted to make sure everyone had a good time. At one point, a guy was talking loudly on the phone for a few mins so the tour guide stopped everything, went up to the guy and politely told him to stop. It wasn't fair to all the folks around him. It's against Trolley policy to do phone calls on the tour.
What made this tour fun (beyond learning some Boston facts) was that the guide would use every add on 'snip it' sound that the vehicle had. At each stop he would push a button to have the intercom play a 'sound bit' telling you to watch your step or watch the branches as you go by, etc. The various advice would be given via recorded voices from Jack Nickolson, John Wayne, Alfred Hitchcock, etc including humor additions.
The vehicle is designed to have you up higher than truck level for better viewing advantage. wide windows for fresh air and many intercoms overhead so you can hear the tour guide. It was very clean. You cannot drink or eat on it. I assume you can grab a quick drink of your water. The seats were comfortable. No seat belts.
The different Trolleys come to the various marked stops every 20 mins. They will not pick you up in-between the stops per the company rules. So don't run after one :)
Our driver was an impressive Boston drive. He swirled around corners and dodged misplaced parked cars, people jay walking, etc.
Keep your ticket in a safe spot so you can pull it out to do the hop on and off feature. We used the included 6$ discount which is given with each ticket to the Tea Party Museum on the sea dock area.
We lucked out with a blue sky, slightly breezing day.
Highly recommend the Boston Hop On Off Trolley Tour. My personal opinion is ....if you plan to stay on board the Trolley for all stops... wait for an older trour guide to hear some good history info. The younger drivers seem to have less to say.