You would be better with the 525, the 520 is underpowered for the size of car. the 525 is the best entry-level engine for the car and in real terms returns better MPG than the 520 due to not having to be worked hard all the time.

IF you do go for the 520, avoid autoboxes on such a small engine as the en gine will be working hard all the time to keep you going, the 525 and autobox is tolerable with the 530 being the best compromise between autobox comfort and economy. The 525 being the best for manual gearbox and economy