If you can take them apart, a wooden skewer is helpful for cleaning off the burrs without damaging them.

I’ve ground so fine that the shot will barely drip out a few ml over a whole minute. Dialing back, I get to a place of optimality, time-wise (17g in 35g out in around 30-35 secs). The problem is that I can definitely see channelling, one area will run faster while other areas will run more slowly, leading to over and under extraction (the colour and speed of the flow is very obvious). I’m using a mignon and I’ve checked that the burrs are perfectly level, I don’t have the large adjuster wheel though. I get little to no superfines, just a propensity to channel, too often to be acceptable. With the beans aging (and changing every two weeks) I am adjusting the tamp pressure to try to avoid channelling, as it appears that finer grinding is leading to more channelling, to overcome the density of the compacted puck? I will try to minimise any other affecting factors as best I can, and see how I get on. Thanks for all your input guys.

I went for the nanotech thinking it should be better, and that the puck would come out more cleanly. To be fair, the puck does come out more cleanly, but I think the nanotech coating does have some effect on the water passing out more quickly (and thus the channelling). The different baskets do come with different hole layouts and numbers, plus the base is flat on mine, not curved to the centre.

My shots before the IMS were actually quite consistent, with little channelling if any, and I always enjoyed the coffee I made (more than many coffee shops in fact). I thought perhaps a better basket might improve things, and it was worth getting it, just to know. I’ll keep persevering (some beans are better than others with it) but ultimately, I may end up reverting to the old reliable basket.