The 118 Birmingham - Walsall route was, in 1973 when I joined the company, operated mainly by Sheepcote Street garage, with some workings from Digbeth and Bearwood - which closed 3 Dec 1973, the same date as Sheepcote St and the route was transferred to the West Midlands Passenger Transport Authority (WMPTA).
Actually a new company was formed for the purposes of the takeover, Midland Red Metropolitan Ltd, which held the assets of the depots, vehicles, routes and staff transferring to the WMPTA's operating arm, the West Midlands Passenger Transport Executive (WMPTE). The former tram and bus depot in Moseley Road was reopened to partially house the erstwhile operations of Bearwood and Digbeth (that percentage of DH's routes totally within the PTA's area of operation, the West Midlands county), the remainder being passed to former BMMO garages taken over at the same time in Sutton Coldfield, Oldbury and Dudley. There was a major rescheduling within both companies to accomplish this, which would be a study in its own right.
To compare a Daimler Fleetline and a BMMO D9 would be like comparing a good traditional beer with a fine wine - both quite spirited (!) and enjoyable in their own way, but both developed in totally different ways towards the same end. The Fleetline was a heavyweight chassis, intended for intensive town service operation with whatever design of coachwork its operator preferred, whilst the D9 had to emcompass both town and interurban work, easily accessible for short-ride passengers yet comfortable enough for long distance travel. Midland Red had since the 1940s tried and tested integral construction, the bodywork not having a seperate chassis but a strong enough overall frame to support the vehicle and its mechanical components, and company-built single deckers from the 1954 S14 type all incorporated this construction. The next generation of double deckers, the D9, also followed this pattern and allowed a 72 seater to weigh less than 8 tons 4 cwt without resorting to 'lightweight' body designs like the D7. Weight saving = fuel saving, of course.
Not quite like carthorses and racehorses to drive, but you get the idea. Fleetlines had a 'lumbering' feel and D9s were more sprightly and slightly faster. One initial problem with the Fleetline was that the driver sat closer to the offside of the bus than in other designs, with the result that as drivers followed the track of the road they were used to, mirrors of parked cars tended to suffer in consequence.
The D9 had its problems and quirks, for example braking was powered by a transmission-driven pump which pressurised the system and held a small reserve of that pressure for a while, but repeated brake applications whilst in slow moving traffic needed to be with a heavier foot or you would 'run out of stop', as a few drivers found to their cost.
The CM6 coaches and a few experimental D9s had pressure storage accumulators built into the hydraulic system (as did the London AEC Routemaster), which holds enough power in reserve for many, many (over 70!) brake applications after the pump has stopped producing useful pressure.
A similar problem applied to the power steering of the D9, which like the brakes was assisted by a transmission driven pump leading to a feeling, if cornering whilst slowing down (e.g. when going round a traffic island) that you could steer OR brake, but not both at the same time. It wasn't true of course, but just the perception given as the assistance given to both steering and braking reduced with speed that either (or both) weren't going to last during the manouevre!
The D9 was overall the nicer vehicle to drive, and not just because one sat away from the plebiscite behind!