Thanks for all the replies guys.
I have taken note of all the suggested pens and will be testing them out over the next few weeks. I'll post my findings on here.
Yesterday Mum bought me a Uniball Jetstream

I can tell you know I think it will be hard to beat.
Price (9/10) I think it was around $4.90 which I find great value for money for the quality of the pen.
Grip (8/10): It has a nice size grip, with a thin rubber outer. It isn't too squishy and offers a solid feel.
Weight (9/10): It is a little heavier than your standard Kilometrico or Bic single pen, but obviously not as heavy as your metal fountain pens. I quite like the weight of it, but that's just me.
Speed (9/10): It is super quick across the page! Super smooth with none of that clicking whenever you press the pen down on the page.
Inkage (9/10): So far I haven't had any of what I call "spiderwebs" where the pen leaks. It is 1mm which I quite like, not too bold, but also not not so thin I have to press down hard to get a solid print.
Total (44/50) By no means am I an expert of pens and this is just my own personal opinion, basically just me crapping on.