The 370 & Versamatic is for the commercial field only. I only know of a few domestic homes that have these uprights as opposed to the X/Sensor based models and of course the X4, X5 etc. Miele's model may well be more expensive but that doesn't mean its fit for purpose in that type of industry. I think Miele should consider commercial vacuums though, but I think they just leave it up to the likes of SEBO, Karcher etc to fill that niche.
A Sebo BS36 for example in the UK has a general price of £330 compared to a Miele S7 at £249 to £300. SEBO also sell a permanent washable dust bag for the BS series.
Vegas - The ET1 and ETH are very similar with only a few differences. The pig tail problems still remain on the K series with the connection plug that slides into the bottom of the electronic handle before the main tube at the top. The tubes themselves have an additional electrical rod that slides down the back of the telescopic height adjustable part with a 2/3 pin connection already fitted at the bottom unlike the separate deal with the C series cylinder vacs. Thus, it has little to do with the actual power nozzle problems.
ET-1 has a brush roll on/off and manual adjustment. It is also slightly larger than the older ET-H.