I gave the Tannus tyres a go earlier in the year after a work colleague was singing their praises.
My first reaction was that they weren't the uncomfortable ride I thought they would be. My second reaction was that there was definitely a lot more rolling resistance compared to the Continental 4 Seasons I was used to running. I found I was putting in considerably more effort (measured with both perceived effort and HR) to get near the speeds I was used to riding on my 30 mile round-trip commute. The most telling point re: the rolling resistance was from another colleague I sometimes cycle to work with - normally on the downhills I would easily gap him, even freewheeling (I'm a lot heavier than he is) but with the Tannus tyres he was sucking my back wheel.
I decided to then go back to my wheels with pneumatics for the summer and enjoy my commutes, leaving the Tannus tyres on my commuting wheels for the winter. After all, I'm sure the tyres would come into their own on the cold, wet, heightened puncture risk rides that come with the winter season. Or at least, I thought that was a good idea...
In the meanwhile my colleague continued to ride on his Tannus tyres over the spring and summer and put a good amount of mileage on them. However, he found that well before their advertised mileage they started to become slippy and he had a couple of 'moments' before finally having an off in slightly damp conditions the other month. He's now decided to go back to pneumatics because it's simply not worth the risk of having an accident, or cost-effective to buy a new set of tyres well before their advertised end of life period - they're not cheap either.
I'm now planning to remove the Tannus tyres (not looking forward to that!) and run pneumatics during the winter (thinking Maxxis Re-Fuse tyres over Conti 4 Seasons) because I don't want to risk having an off.