Good Car "Watch out for expensive exhaust"!

I bought my 2004 1.6 Zetec model about 4 months ago and generally quite happy with it.Practical Car that generally feels good on the road and returns good MPG around town.
Caution! I have had to replace the full exhaust recently and the quote nearly knocked me off my feet! Over £500 for an exhaust including the Catylitic Converter.This was the cheapest quote of four and it carried a 3 year guarantee," For £500 I felt Budget should have gave a years road tax and a full tank of fuel"! But C,est La Vie.
My only other concern is the front end handling,taking bends/corners at reasonable speed the steering becomes light and unpredictable.I previously owned a Mazda 323 Sport so the step back in spec is maybe hurting a bit but I do think the Front End is ropey especially in the wet!
I hope this helps!