De Jong is better than Cabaye all round, but Cabaye did well for me at Lille. His wages and everything are less demanding, so he would be a good backup for Hamsik; not very good holding midfielder though.
Get De Jong, but offer his agent a lot of money and him a lot of 'signing on fee' and lower his wage a bit, to around £45k. And play De Jong as Ball-Winning/Defend with Hamsik as Advanced Playmaker/Support of Attack.
So yeah, De Jong is a lot better overall and should accept a lower wage with a big 'signing fee' - just make sure you bribe him and his agent!