Yep, the original wash head was probably the best performing of all. I did find it backbreaking to use though, having to stoop in order to keep it at the correct angle against the carpet while also working against the suction of the machine. In those respects I found the Ultra Rapide much more comfortable to use.
The original wide wash tool was great for stairs though, so I bought one to compliment the UR head. Much quicker and easier than trying to clean a full flight with the dinky little upholstery wash tool.
Carpet dryness is an issue I noted with the current Vax canisters. The suction opening on today's wash head is quite large, whereas the original and the Ultra Rapide both had a thinner, narrower slot that concentrated the suction better. The old clear wash tool was also designed in such a way that it was virtually impossible to overwet the carpet, even if the user was negligent. Because it sealed itself down onto the carpet, and had suction slots fore and aft of the liquid supply, the solution kept circulating at all times and could not puddle underneath the head. It really was quite clever in how it enabled everyday members of the public, who had no training whatsoever, to wet clean their own carpets with very minimal risk of damage.