I've got one fitted to mine (97 Mk3 2.0l 8v) and to be honest, i wish i had'nt bothered now. It was really fiddly to tune, the locking ring on it would always keep coming undone, causing it to untune and give me horrible fuel consumption and a constant rasping noise. When it would stay tuned, the gurgling noise (this is normal with it) was very intrusive, so i fitted a pipercross filter designed to mask this but i found this barely made a difference. My friend fitted one of these to a clio 1.8 16v and found the same problems as me. My opinion is not to bother, as mine spends its days screwed shut now.