Looked into the GP20s after reading this post. Prices are very reasonable when you compare them to many of the competitors, and I doubt anything offered by anyone else would be notably better, Maxtons got some pretty serious credentials. Can't wait for your take on them.
DMX said exactly the same about Maxtons price/performance ratio. So much so they have decided they'll HAVE to match their price when they start making cartridges next year. They have put Maxton as their "muse" in terms of future road products.
I have just been for a post installation run. Was not pushing too hard as I also had a brand new front tyre on.
First point - the static sag (bike upright on wheels - no rider) is almost exactly half that of standard forks - actually more than half but only just. Now 20mm instead of 44.
So the headstock sits higher. Some of this in my case counteracted by the lower profile tyre. I say this just so folk realise - headlight adjustment is probably required after. This static sag is actually PERFECT for me. They were built to my weight so I suppose that was to be expected. So pre-load adjustment would for me have been a waste of money.
Once moving, well things are notably (as expected) better. Even fierce front braking does not cause stupid excessive nose dive. Over small ripply bumps they're smoother. Over potholes - good too.
Only "speed bumps" really gave them trouble - but even so they handled them far better than stock.
Under harsh acceleration there's little or no rise and fall at the front end. Sadly however this part of the test was curtailed by acquiring a police "escort". When we parted company they did give me a thumbs up though.
Only have one niggle - but it's rebound related and can be adjusted - every so often banked over on not so perfect surfaces there is a tiny bit of float and it steers a bit wide. This however at corner speeds easily 10mph faster than I'd be on stock forks.
Once the tyre is scrubbed in and I take 1/4 turn of the rebound (I went to see and pay DMX on my run and they advised back a 1/4 turn off) I think they'll be good for as much as 20mph in bends. That's actually a bit worrying.
There is however now a more serious issue. Even though I have good rear shocks - The Maxton forks may well force me to re-upgrade the rear too. I'm off to check the Fournales pressures as soon as they cool down.
I'm reluctant to eulogise too much - but definitely an investment - and I wish I'd done it sooner.