They are in the boot of the Infiniti's.
Q50 was a good example, you lost some of it in comparison to the diesel and non hybrid variants.
The 3.5h is AWD, battery is about 2k to replace but should last around 8-10 years.
I can't remember for sure but again the 3.5h didn't run for very long at all on battery only.
Gearbox layout is different, engine is N/A and it still uses a wiper motor for hicas, steering can take a bit of adjusting to, besides that nice place to be and it's what swung me to be a little more optimistic and open minded.
I personally am all for using hybrid technologies for more power, however that is something I believe is pretty hard for the aftermarket tuning side of Q50 3.5h, from what I gather you are limited at catback exhaust before it starts having kittens.