I think the speed control is one of the reasons I kept the Miele, it may have some toasting electronic components, but it is handy to set it to the lowest setting for quiet cleaning or for cleaning the dust out of the vintage things I have, or to full whack to clean out between the gaps in the living room's floorboards (though for floor cleaning like that, I switch between that and the Tristar, depending on what I fancy using that day)...
The Miele does have a suction relief valve in the handle is also handy, but the noise it makes is just plain annoying, it's like a high-pitch whistling coupled with someone constantly blowing through the remains of a burst balloon, and of course has the habit of opening by itself somehow, if it wasn't used, I'd tape the damned thing up!!! :S
I need to open up the miele actually, just to check on those toasting components, just to make sure they're not going to catch fire any time soon... :\