Hey Charles, apart from the shakeout back and a heavy-duty (and presumably longer) cord, I believe the 334 was no different mechanically to the other Convertibles.
I think you make an interesting point about the cheaper machines. I noticed that in the Consumer's Report posted on here from 1959, there's a very wide gulf between the price of the model 31 and 66 ($40!), especially considering that mechanically they were identical. I guess the cheaper machines were maybe 'loss leaders'.
Si, funnily enough, I was pondering the tool conversion on the Seniors/Convertibles this morning! I did try modding a Senior a couple of years back, but my pan converter was damaged (I hadn't realised, as it was the only one I'd ever seen!), so suction was still lousy. I have plenty of free time at the mo', so I think a tinker is in order again!
The side-converter cleaners aren't sealed either, but when using my 160 today, I noticed that when you cover the hose end, the pitch of the motor does go up, and the bag 'twitches' (like on a Junior), which quite suprised me. Suction is better on the 700/800 series though. I spent today blasting dust bunnies out from behind my radiators with the 160, now it's getting cold enough to stick the heating on...
The annoying thing with the side converter machines is that you can't pull them along, which toolkit d'you have?
(other)Si