Armchair Captains this is for you :
 

https://youtu.be/Nu459tnPiVU

What do you all think ?

Unstabilised approach, good decision to go around.

Yep...
 

...chuck it away and wait a while before having another go. Can't fault that.

A normal day in the office.

C**p conditions, good decision, good airmanship.

A go-around followed by a missed approach by a pilot who was on the ball.

Good decison, good airmanship.
St. Maarten it looks like.

Why was he so far off the centre line? I assumed the guidance systems would have had him better lined up than that? Was pretty awful conditions...

Looked like a bit of windshear on short final.
Good decision, well executed G/A, what we're paid for!

Why was he so far off the centre line? I assumed the guidance systems would have had him better lined up than that?

I assume the guidance system in use was Mk.1 eyeball, so good question; unless as others have asked a shift in the wind at low level. I was amazed that there were people 'on the beach' in the rain.

They look lined up to me except for the last couple of seconds which is why the crew initiated the go-around.
Approaches show only a couple of degrees offset from runway heading.
Looks like low level wind shear.
Again, there's nothing special about this and it's what 'we' do.

http://www.eddk.info/Download/PDF/TNCM.pdf