No antivirus on the market will detect everything out there but there is a submission process where you can send in samples of malware for analysis and addition to the database.
There is no need to 'fork out' for any extra protection where there are loads of free anti-spyware applications available. But if you do decide on that, go for the 'Basic Protection' as the higher models incorporate antivirus also and having 2 of those on your machine can actually let malware in.
Personally I prefer SpywareBlaster and Malwarebytes free.
Thanks for the reply.
I already use Malwarebytes which successfully removed a recent scam attack ( once again
McAfee didn't spot it ).
Point taken about multiple AV products.
OK, good luck.