[Pj]

Well now...

We have used 2 Bentley brushes for about 4 weeks

Our conclusions:

Ground floor was the best test because we could see what we were doing and the results were fairly easy to see. 

Good flow from 2mm jets. 
Brush very light
Sweeps right to corner easily.


2mm jet flow gives no advantage as waterflow down glass is not enough water volume to flush sticky deposits quick enough.
Brush too light, so glass gets missed in places unless excessive pressure is aplied, thus extra pressure.
Hard to use force on brush from pole extended beyond 4'.

Well, theres the results.
Argue if you like, but that is what we found.

Conclusion?

Probably like trying to eat food with teeth missing.
You can get through it if you have to, but you just don't get it all properly.

[frames to panes]

The idea of using a Bentley is to reduce the weight on the end of your pole. So if your cleaning at forty or fifty feet the weight advantages come into their own. If your only cleaning at short reach then the heavier brushes are not a problem and will clean better. Some poles like the Superlight would be very unbalanced with say a Vikan sill brush waving about on the end. 

[[GQC] Tim]

True, but I can see some people say that a brush too light isn't too good either, exactly for the reason Pj posted. If you need to scrub hard, and you have a bit more weight on the brush, it might make it easier? (Coming from a trad guy, so don't know)

I do agree that the Vikans are too heavy, especially on an GF X-tel, it get's quite floppy in more horizontal positions.

[cybersye]

I've had just this problem too, since changing to a 40 ft emporium modular and bentley brush, so much so a couple of customers have picked me up on it, guess I'm going to have to scrub and rinse a bit more on a few of my jobs! I was previously using cleantechs own yellow brush which i rate highly and always did a good job, I've yet to try it on the modular but I'm thinking it will be too heavy. I'm finding that with the pole and brush being so light I cant get enough pressure and the bristles to spread out enough. A minor problem though as its definately made my 3rd and 4th storey work so much easier.

[Ian_Giles]

On dirty windows, or ones that are well weathered and not been cleaned for months I would agree the Bentley isn't the best, you have to scrub a lot, side to side and up and down to hopefully clean every inch of glass.

The 2ml jets though are fine, as for flowrate, if I wanted I could have the water jetting 20ft, which is WAY too much!
I cope with a flow that gives a jet of about 4ft.

On repeat clean work the Bentley is fine, used with a carbonfibre pole, the low weight allows you to scrub quickly as there is little inertia to overcome.
Dried on bird poo is a pane though
And as has been said, the higher you go, the advantage of using this ultra light brush becomes more apparent.
It only lasts about 6 months though, so it isn't very hard wearing, but then, it is as cheap as chips to replace anyway.

Ian

[Bonzer]

I tried the Bentley brush last year for about a week, before I gave up and went back to the Vikan.

It is lovely and light, but I found that with jobs that always used to come up great before (plastic frames,cleaned every 4 weeks for over a year), the Bentley left spotting. I didn't know whether this was down to the flocked bristles or the lack of scrubbing firmness of the bristles but I know that as soon as I went back the the, seemingly, lead-filled Vikan, it was fine.

[Sir Squeaky]

Well I think it's excellent, so there.

[frames to panes]

I've found the Addis mono a better brush for the same weight. Splays very well with less pressure and seems to have tougher bristles that scrub frames cleaner. Don't EVER put it in hot water though. :