DH has a major car seat hangup (which has expanded to me a bit as well), and we rode the Minnie Vans twice. Drivers take a week long carseat course and both were definitely pros - they sized up my 6 and 3 year olds (6 was petite, 3 is a big boy) and grabbed the seats out of the back and had them installed appropriate for each kiddo in no time. I was impressed that they had me get my kid into the seat but then I could see them very discreetly check that things were done properly (chest clip at shoulder, snug) before hopping into the drivers seat.
Since we won't take Uber or Lyft due to the carseat issue, Minine Vans were a lifesaver and a huge help. We went from BLT to Beach Club in twenty minutes, when before that would have been an hour long bus adventure. The other trip was an emergency crabby toddler evac from DHS and the driver even made toddler happy.
And yes, they are one of those super convertible carseats - ours were forward harness and booster.