The tricky thing with tyres is that there can be so much variation between two sets of tyres, even of the same make model. This can be due to many reasons even down to the time of year they are made.
My point is, they are both good sets of tyres with good reviews, its a bit of a 50/50 chance of which ones you buy will be the best, so unless you buy both sets you will never know which is the best set.
If you really want the best set then have a look around and look for reviews from people with Golf GTIs, however don't stress about the decision too much as unless you are going to be driving the car on the limit all the time you will not have any trouble with either the yokis or the toyos.
Hope this helps.
PJC