Buying a fast estate - Octavia vRS or Focus ST?

Which petrol estate is better - a Skoda Octavia vRS or a Ford Focus ST? Also after I buy one of them would it be worth putting a chip to get more PS and torque?

When should I change the oil in my Focus ST?

I'm collecting my new Ford Focus ST this week (the petrol one) and like virtually all cars nowadays, there's no running-in service with the first oil change being scheduled for 12,500 miles or 12 months....