Thanks for the comments, appreciate the help.
I have time to think about this, as both the
jointer, and
extractor are still out of stock. I was in the store recently, they reckon it might be in stock for January. It's true it's one time cost, and it would probably hold good value if I was to sell. So that gives me some comfort. Warranty is also a benefit of sorts.
I've heard about VFD's, but didn't really know what they were. You learn something every day, thanks for that. It could work as a package with used 3 phaseblower, and the VFD as an on-cost, and still possibly be cheaper than the new one. But I would likely need to spend another £200 on the good filter. That would just about make it even, or slightly cheaper then new solution.
One last question about the air flow... Lets say I buy
the new stuff, which is capable of 2x100mm or 1x125mm at the cyclone inlet. From previous comments, there is a significant benefit of bigger diameter. So I would run single hose of 125mm diameter all the way to the jointer, where I would have to choke it down to 100mm. I've studied the pictures, I won't be able to open it up more. Also due to the nature of the jointer, where the ducting is flipped left to right depending on the mode you have set up, I would be running flex hose. So I know that will kill performance once more. So maybe that on it's own is better larger. And the question: is this choke at the jointer going to kill the performance to a degree, where it's going to be as bad as having full run in 100mm? Or is there still going to be a benefit to the 125mm pipe?