To be fair, the genuine ones have 'made in china' written on them. Unipart filters are what I've always used and never had any problems with the quality or performance.
The more crucial parts, timing belt kits, tensioners ect I always use genuine.
I gave the bloke my reg and the system came up with two parts. One with an internal valve and the other without. Both identical fittings which is why he advised me to find out which one I need.