I Google translated lots of the massive mtb-news.de thread about shigura to find any shortcomings. The only thing I could find was that the pads sit quite close to the disk, which to be fair is a magura problem and nothing to do with the Shimano lever.
The other thing is that the master cylinder in the Shimano levers is smaller than the equivalent magura, so when the pads are nearly worn out you can pull the levers to the bar (it happens gradually so you do get a bit of notice!) I thing to overcome this you can intentionally overfill the system or use thicker disks (the magura ones are thicker)
I bought the bike discount MT5s, €150 for 2 full brakes with massive hoses! (€190 with disks) I’m assuming they were 2018 model?
To be fair I’ve only used them for a couple of rides and I’m comparing them against an old set of SRAM guides (fully bled) but the power is a big step up. I guess I’ll see how they hold up over the winter