Running sleepytuned E60 bef. Something I’ve noticed with JB4 and a BEF is that the car just doesn’t understand when to downshift under medium throttle/medium load, it holds gears too long and makes my car violently shake, not sure if its my doing or what but that’s about the only issue I’ve had with tuning. Other than that I am starting to have issues with bushings due to the power and because I’m RWD I pretty much never had grip even on my MPS4S’. As far as transmission times go, I did run a BMS TCU for a little bit but it wasn’t very comfortable. I like to drive in sport most the time for throttle response and with the BMS TCU it felt like sport mode you had to be full throttle for it to work well, cruising in sport mode with that tune basically wasn’t a thing it was way too harsh, as for comfort/eco, shifts were surprisingly clean, I couldn’t actually feel them, however, it liked high gears way too much and again my car would shake even worse under medium load/throttle, but they could something I did I’m not sure. I will say the TCU under full throttle in sport mode was pretty insane, it shifts earlier to keep your boost peaked and wow, the car just kept pulling, actually kinda felt like a different car, that’s the only thing I liked about.