Thanks for all the comments guys.
As mentioned it is a company car so not too worried about the insurance or other running costs other than fuel.
Have ruled out the Toyota as I have had a look on Whatcar and it only rates it 2 stars, the spec is no better than the Leon or Golf and the engine in it sounds woeful (13sec+ to 60 from a petrol!).
The Leon is a the same spec as the Golf (same toys etc) but has the 105ps 1.6tdi engine. Comes in at £42/month in company car tax.
The Golfs both come in at just over £50/month in tax. (petrol is £52/month and diesel is £54).
Turns out there might be the option to pay a little bit a month and go up a car grade in which case I could get the Golf Bluemotion which is £39/month in tax so offsets the extra contribution a bit and comes in with the 105ps diesel engine. All the reviews I have read about these have been good.