I own a 20 plate 1.5tsi Octavia SEL dsg estate, it's my 3rd Octavia. I bought it a year ago, it came with 17s, as standard. I sourced 4 decent used late MK 3 facelift Octavia alloy wheels, fitted those for comfort. I've also fitted 4 all season tyres onto them, too. I see a few positives from this, tyre choice is larger & tyres are cheaper, than the previous 17s. You would also gain on fuel economy, marginally, too. Also comfort levels are marginally better, compared to running with 17s. You will notice a bit of a difference with comfort levels, hitting potholes, but it's not a massive difference, more of a subtle change. I've done this on few other cars, previously, down graded their wheels to gain more comfort. Bit more pothole & kerb resilience, too. I've also stuck with the 91 load ratings for 16s wheels from factory for my car. I'd never fit higher load ratings if not required. I prefer higher spec trims, with lower spec wheels, mainly for comfort, not vanity. I've also informed my insurance, there was no extra charge to my premiums.