any one done one of these in an 1.4mpi 8v.

if so any changes noticed?

I havent. In fact I'm not sure they are availible for the 8v engine. I do have some experience with them in previous cars (Capri 280 Brooklands) and it was estimated that they only give about 2-4 bhp on their own. It makes sense to pair them with a free flowing exhaust and manifold , then the engine can breathe in and out more freely , liberating a bit more power , again though , I do not think such parts are availible for the 1.4 8V Skoda engine , I would happily be proved wrong though.

they are available just wondering if its just more drivable not bothered about bhp if I wanted that I would by something with loads of cylinders and lots of displacement

I'd be surprised if you noticed any difference, aside from the noise, compared to a standard paper element

Chris