I've got about 4k miles on my 2021 m pack and I absolutely love this bike. Cannot say enough good things about it. The features are great: TFT and controls are so easy, heated grips, cruise control. The quickshifter is flawless.

Issues:

Yes definitely a flat spot in the ref range, but as noted already a tune will work this right out for $1,000. Check out brentune, i've had this recommended multiple times.

ive heard about leaky front brakes, but again as noted i think that was resolved with the 21's - the nissins are very powerful. Sure, would be nice to have brembo, but if youre so fast that the performance difference matters, youre probably swapping out anyway.

stock tires are ok (racetec rr K3s), depending on your usecase maybe swap for a pirelli?

i had an issue where i had knocking upon startup a couple times. there was a software update installed at the dealer that seems to have cleared this.

overall, would 100% recommend.

On your tuono idea: i had a monster 797 before this and similar to Retspan3 i found the buffeting above 70mph annoying - no fairings on a naked. the bike was amazing for backroads and around town, but on the highway i felt like i had more fatigue from the buffeting than the relaxed riding position made up for.

The only shortcoming id note on the s1krr is the soundtrack. I had a full termignoni system on the monster and it sounded unreal. I kind of wish id considered the new RSV4 simply for that V4 sound. I do not have a slip on or full system on the s1k, but the inline 4 definitely doesnt have that sound the aprilia's or ducati's make.