'the very best of' eh? Never liked that term - very subjective.
I only bought this because (I'm pretty sure) you can't find the remix of 'midnight' anywhere else. So I was happy....it's not that expensive for one rare track.
However, if you need advice on whether to buy, it really depends.
If you're already a big Magnum fan - you'll have these tracks already (except midnight).
If you don't know Magnum very well, then yes, it is a reasonable collection to get you going.
The songs are mainly the bigger single hits and trusty live stalwarts.