I have tried Maggi soup some time back. it tastes just ok. Not really great as I would have expected from Maggi. I think Knor soups are better and have got a lot of variety. So, I would recommend you to buy knor and not maggi soup.
The maggi soup should also try to provide more variety of soups, currently there are only a handfull of them. More variety means more options.
You can try once and make your on judgement as every1 has different taste buds.