The Mégane II Owners' Club

While researching tuning options for my
06 megane cc 1.9 dci 130 I was looking at companies offering remapping/ ecu tune.
As well as a remap several companies offered :
DPF removal
EGR removal
Speed limiter removal

Can anyone please tell me pro’s / con’s of these last 3 options?
I didn’t even know that my megane had a speed limiter. What exactly is it ? How does work etc ?

I’m quite new to all this tuning so please forgive my ignorance.

If your car is meant to have a DPF (Diesel Particulate Filter) and there isn't one it will fail the MOT - don'y do it, unless you keep it and are prepared to replace it for the mOT

EGR (Exhaust Gas Re-circulation) similar to above takes out some of the potentially harmful pollutants before exhaust, I don't know the technicalities re: MOT on this one and you would have to investigate.

Speed limiter, as above I don't know the technicalities re: MOT on this one and you would have to investigate.

Whilst 1 and 2 will certainly give you a little bit more power they would all have to be coded out of the ecu or else it would throw up an error and probably affect other things and could even mean you drive around in limp home mode (low maximum speed, high fuel consumption, no cruise control etc).