I've tended to never use Sport mode on the car settings as although people on here say it makes a difference to the pedal response I didn't notice any real improvement in response and the noise from the soundaktor thingy just sounded like the car had a misfire! Yuk!
Instead I just have most of the settings on normal (I find the steering a bit too sharp in Sport too, I drive quite a variety of vehicles over the course of the week and when I jump in the Golf with the steering on sport I'm overcorrecting all the time - I probably look like someone on one of those 1950's movies where they're sat in a car having a conversation with a green screen backdrop behind them sawing away at the steering wheel despite the road scene being dead straight!!!)
I've used several settings on the Pedal Box but keep it on a fairly mild setting generally which is the most user friendly but still gives a pretty instant response. I've not tried the really extreme setting but didn't like it on the Sprint Booster I had previously as it made the car really jerky. Maybe if you were doing an all out performance test you'd switch in into the best mode briefly but doubt you'd be able to live with it for long.
I'd think if you were running a DTUK FSR with the Pedal Box on an extreme setting your front tyres wouldn't last more than a day or two but you'd have a massive grin! Seriously though, like most of these settings, be they the car menu or the plug in modules, you have a play with them occasionally but find your preferred setting quite quickly and stick to that as it suits the roads and driving conditions you deal with and driving style too.