Everyone will have a different version for whatever product they are trying to sell you.
The ECU does, like all modern vehicles, have long and short term fuel trims, up to, let's say +/- 20%. So a standard car lives somewhere in the middle of that scale. It's there to allow for different conditions, such as fuel quality, inlet temperatures (and therefore ambient temperatures), planting your foot down under load, etc. Put some dodgy fuel in, you might need, maybe 10%? Take it on track and show it a good time, another 10%?
Now fit some new hardware. You're probably going to need some more fuel for all that extra air you are moving. So your new baseline now might be +10%. Now you've only got 10% left to play with. You might get lucky and the ECU can run things OK with less trim available. You might not. It might be fine until you do that hard drive on the hottest day of the year and you could only get standard unleaded fuel.
Why wouldn't you remap to make the most of the expensive hardware you've just purchased for your expensive car? Or leave it luck. Just one of those things that only you can decide.
We know that the upgrades that we sell are tested and proven. I don't know about any others.
Dave
Yep, that's a fine plan. I'd always recommend remapping, as per reasons above.
Dave