Well after much deliberation my wife and I decided to take the plunge and have had the 15 year old Baxi replaced. It never had a pre heat function on this one as it was the early model not the 105 instant. We have had a Worcester Bosch 8000 style 40kw fitted in Black. We have noticed that the hot water delivery is very very quick even without the pre heat turned on. The Baxi had been a good boiler but was just tired.
No more warranty payments now as this one has a 10 year parts and labour included with the price.
We are still getting to grips with the digital display.. Lots of features with this one.
Thank you to all for your help over the past few weeks 👍