As an advanced DIYer I bought a side loading drum mixer from B&Q in about 1982, by about 1990, the drum was perfect but the big bearing for the drum was shot. Basicaly when you tip the drum up for storage, rainwater just runs into the back bearing, which then rots it. When this became apparent I then fixed a ali shield (could be a plastic bag over the back of the rum so the rainwater does not run into the bearing (stable door and horses?)
When I bought a cottage for refurbing (300 miles from home) I bought a Baby Bell 130. which I have used to lay about 20 cu m concrete and several tons of rendering/ pointing etc. I hate the b**dy thing but it keeps on working! My criticism of it are no way of altering the angle of the drum to optimise mortar mixing. When the drum is full of concrete and is on its stand (essential for wheelbarrow use) the machine rotates about so it has to be tied to keep it at the correct position for shovelling in ballast. Also as it has a non reversible gearbox( worm drive?), you have to fiddle about a bit to stop the drum in the right place to get the mix out without having to fiddle about around the "mixer" bars.
My originla mixer is still going, even if it rattles like a good'un, variable angle of drum and the drum can be contrarotated by hand to get the concrete in the right place in it. Another good feature is that because it has a proper frame to it , I built a chute, so I can fill a buckey from it by tipping with out dropping any mix on the floor, simply not possible with the Belle.
Frank