Its a subjective question - somebody will be along to say it's fine...
But I can offer my opinion on the Cobra non-res cat back that cam on my DSG Gti - it was not pleasant.
Too loud, droning on the motorway and it was so loud it made me very conscious of my neighbours each time I started the Golf up early in the morning - only place it sounded good was underground car parks.
Ended up having to get a silencer added to get it down to a reasonable volume - I went to a specialist exhaust maker to get this done, I think it would have been cheaper contacting Cobra for the Resonator section. After that I was happy with it, rather than all the time, it is loud when I want it to be.
I would say the quality of construction is OK - on a par with Milltek - but the clamps that come with the exhaust are not the best.
I have since adding a sport cat downpipe this has made it a bit noisier but its now got a nice burble and pops on over-run + DSG farts are great!