I bought and installed one of these from the same seller about 2-3 months ago.
It was a bit if a stretch to get it on but length and heightwise it's probably 90-95% there are small gaps on either side where it meets the bumper but maybe only 3-5mm.
The only 2 issues I had with it were that the top lip is too shallow and therefore there's about a 1cm indent from the bumper to the diffuser. Enough to notice if you know it's there but not a huge issue.
The other is that there are some imperfections in the weave like folds and different colours but once again, if you don't inspect up close you won't see it.
I notified the seller of these and they offered a partial refund. In the end I got it for a great price for it so I'm pretty happy. Hopefully they took my feedback into account and fixed the mould a bit.