How would you stat a rotating detonation engine?

[Say, it isn't that bad!]

Since I didn't see this as an option when searching Spaceships. Although I understand the idea, I'm not sure how to explain it, so here's an explanatory video:

https://www.youtube.com/watch?v=rG_Eh0J_4_s

It seems sound, with the only challenges being engineering challenges. That being said, it is definitely a complex engineering challenge that requires a lot of precision; but not one that would seem to require any new science or "super-tech". To note, I am simply an interested layman who watches videos by people like Scott Manley, so informed opinions are definitely welcome. ;)

The optimistic efficiency increase estimate seems to be +25%; so I'm estimating down to +20% efficiency. Doing a square root on that to get an acceleration increase gives 9.5%, which I round to 10% in the following write-up:

Rotating Detonation Engine (TL9) [Rear]

Any non-nuclear rocket engine may be made a Rotating Detonation Engine (RDE). When applying this option, you may choose to either increase the maximum delta-v of the engine by x1.2, or the acceleration of the engine by x1.1. An RDE may not be a *variable-thrust engine. If the RDE option is applied to a variable-thrust engine, the engine becomes fixed thrust, and you must choose the thrust provided by the engine when it is created. The cost of these engines is increased by x2**; in addition, an RDE may explode on a related critical failure due to the shockwave becoming uncontrolled.

* Given that the shockwaves require precise timing as they travel around the chamber, and have to move at a constant speed, variable thrust does not seem at all compatible. However, at least most variable thrust engines can be set to a constant speed; which eliminates this incompatibility by way of making the variable thrust engine a fixed-thrust engine.
** This is an uninformed guess.