I've just taken the Polo for a quick spin, despite the tracking not being done or the exhaust completely sorted - I couldn't help myself

Really impressed with the pick up and pace and as for grip - wow, this will take a little getting used to! Reminds me a bit of being in an old friends modified 106 GTI!

However, whilst driving down some very straight country lanes I thought I'd check to see how much of this compensator non-adjustment is an issue - ie, will the rears lock up under heavy braking.

Well all I got was a bit of a shock as to how well the car now stops, the rears didn't lock (to be honest they're probably shagged anyway) but what I did get was a VERY odd noise from the front brakes, almost like a grinding squeal but not exactly high pitched. I drove a little more and applied the brakes, same again, so pulled over

Well the pads and discs obviously get hot, smoking hot in fact!

Is this likely to be just a burn off of the materials left from the manufacturing process or usual when putting a 'heat cycle' through the brakes? Any ideas on the noise?

Brembo vented discs, EBC YellowStuff pads

If you were doing a lot of heavy braking that's OK. Just remember to keep moving after you get them smoking hot for 10 mins till they cool down. Don't ask me why it's just what you do.

I've had yellowstuff pads smoking before on a track day it's no big deal.

Sometimes when brakes get a bit squeeky or loose their bite, getting them smoking hot can help bring the friction surface back. It's something I have to do on the wife's Audi A3 'cos she doesn't drive it hard enough!

Keep up the good work!