Is it a cup or not??? (RS225)

It could be a full fat like you say, only way to find out now is to take it to a rs specialist and they'll be able to tell you after having a look at the suspension

 

I rung up the HO and asked exactly what my car was as my insurance company needs to know.He first looked it up but like all the other dealers could not work out it out as it just came up 225 but what i had on it was more than that but it was not a cup as the internals were not the same but looking at the photo he said it had a different nose shape as if it was a cup and then it had the multi spoked wheels etc etc etc. He said he gets these enquiries all the time about the late 225's and cursed the DVLA for not putting enough info on.
He said he would send pictures and obviously plate numbers and vin number etc etc.
gave me a ring late next day saying it had the Cup chassis option + the Climate control option and Xenon lamps option. The cup chassis he said which had been sent to him basically fixed the problems with the handling like stiffer suspension + a few others and was obviously the Cup on the outside ( hence chassis). The other stuff was optional extras over the standard Megan 225.
But here is the thing that confused the guys who built the thing as 'Auto' Climate control was only with the Trophy at the time mine rolled off the line and yet mine had it. But apart from that the rest was what it is. I like it because you get the up rated mechanics sorting the standard out plus where the cup is obviously lightened so it is a bit bare inside the option was taken to upgrade as if it was the normal 225 so in effect the best of both worlds.
Yours does sound very similar but give them a call and they will give you the exact package you have however now being told its not a cup by a reputable source as i was see if the traction stays off if it does it's the cup chassis if not its not it really is that simple now....

 

Eibach are standard