For those who might install / use this product, I thought I'd toss in some information, as I just finished an install today.
I tapped into the signal control wires just behind the headlight. Rather than use the plug-style adapters they provide (they don't seem to crimp to well, IME), I just cut, stripped, hand-twisted the wires together, shrink-wrapped each and then re-wrapped he entire bundle of wires with electrical tape. This saved a little space compared to using the plugs, which was important because I didn't tap very far deep into the wiring, and couldn't afford to have a big bulky chunk of connectors, space wise.
I chose this b/c I already had a 12V tap right there (a double USB port with outside temperature that I added a while back) and found I had a good mounting space for the accelerometer in the storage area (see below).
And reading the OP's comment about difficulty in initiating the turn signal (I noticed this too when setting things up), I used a pair of pliers to compress the two spacers that are provided, and it seemed to solve the issue.
The wiring was the same in my 2020 DSR, which is great, but according to the unofficial manual there may be a different relay at work in my unit vs. previous. This seems like it's even better, because (I'm guessing this is the relay being different) I can terminate the turn signal if I like, but just pressing the switch a second time in the same direction. There is no waiting for it to self cancel if I change my mind about a turn. This a GREAT feature b/c it allows you to easily stop unwanted turn signals which is important b/c those can happen when navigating new territory (and not sure where to turn).
I mounted the accelerometer unit in the storage compartment, which may not be an option for those with a charge tank or power tank. You'll see in the picture I'm attaching that it's just in front of an EVTricity 3.3 kW charger (FB Marketplace purchase) that I mounted there which works great, because I can still store some things (and not have them lost in the bottom of the compartment), and I can charge at 6 kW in total at one charging station using the built-in charger, as well as that one. I just used heavy duty double side tape (Gorilla glue brand) and it's just barely pinned under the charger, so it's not going anyplace.
It is at a bit of an incline: Correct side up, pointing straight ahead, but I saw that kind of orientation in the official STS install video and figured I might lose some sensitivity, but it seems to not be much.
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As far as performance of the unit, I just drove around the neighborhood a good bit and took 20 or 30 turns. It works decently well. I would say maybe 10% of the time it doesn't cut the turn signal off right away after I made a turn (lingers for 2-3 sec), but also it terminates perfectly if I make a turn from a stop or do U-turn (no lingering turn signal once I hit a straight-away). As I said, I can terminate on my own by pressing the turn signal a second time (when it's still blinking), as opposed to pressing the button on the center (as it's done to terminate a blinker in the stock set up). Small learning curve there maybe, but I believe I've ridden MC's where that was how the signal was terminated anyway. (Seems natural.)
Overall, I dig it. I have the tendency now n' again to leave my blinker on (maybe 5% of the time), so I'm hoping that this will reduce the possibility of a false signal causing someone to pull out in front of me.
-Scott