what ya just said is what I thought but didn't want to here it , my reasons was ,, takes a long time to heat up , the top pipe from the rad seems to have little pressure even at 90dg... its only the cost as thats one job I wont do as it means taking all the cambelt side off..
ive also had a high squealing noise which is also associated with a leaking water pump but it does not over heat and will stay on 90dg