Fly Wheel - Zetec

I'll give my opinion which works and the reason.
First off, those that go a 1.8 flywheel and get it drilled for a pinno clutch are going backwards, a pinno clutch can handle about 130bhp, ok so get updated clutch, great now your at about 200bhp and clutch is hard to drive..
Remedy is to keep the zetec fly and clutch and either lighten that or
option 1, spend big money on a special UK unit but they often still use pinno clutch.
Option 2 , eyeball the USA eBay for a zetec ally flywheel, yes ally,(aluminum) it takes a Focus zetec clutch which works perfectly in Escort with type 9 box. A stock zetec clutch is rated to 160bhp but I've had higher power with no drama , biggest plus is it's the same spline and depth, no messing around. All you need to do is space the starter back 12mm to engage ring gear.

Does it change the characteristics of driving, yes heaps and worth it.

Brands to look up are
Fidanza
Spec Clutch
There's some that pop up second hand occasionally, it might need a new friction disc but rare..