Quite true - as of April 5th 2005 condensing/high efficiency boilers will be the norm. There is an incentive scheme running at the moment which helps with the cost of installing a new condensing boiler - bet your plumber didn't tell you about that did they? Details are on
http://www.a1-boilers.co.uk/npower/index.htmlCondensing boilers did have some teething problems in the past but manufacturers have solved 99% of these now (such as corrosion) and we find that we have fewer problems with the condensing boilers we fit than with the conventional boilers! One thing to bear in mind though - condensing boilers MUST be serviced/maintained every year. The condensate trap can potentially block causing a build up of slightly acidic condensate within the boiler which will rot it. Yearly service - this will not happen and the boiler will be maintained at its optimum efficiency (requires the use of a flue gas analyser) - saving you money on your gas bill and CO2 emmissions which is the whole point. With the rises in gas prices a condensing boiler is a good investment.
If your existing boiler is still working ok and you can get parts - why replace it. Contact a couple of your local parts centres (HRP&C) and ask if parts are still available or if suitable equivalent parts are available (manufacturers are often quite keen to sell you a new boiler too funnily enough!!) We are still maintaining boilers which are over 22 years old. They are not efficient, and probably cost the customer more in gas over 3 years than the cost of the new boiler (trade £ unfitted) but it is the customers choice.
If you feel that it is necessary to replace your boiler (either this year, next year or in 5 years time) then do so. A condensing boiler should not put you off. They are reliable and fuel efficient. Pay a little more and go for a good make (stainless steel heat exchanger) a Vaillant Ecomax Pro would be a super easy direct replacement for your Potterton Flamingo. We have already fitted over 80 condensing boilers this year alone and we haven't had a single problem with any of them. Over the past 6 years we have only had a handfull of problems - and that was early days.
The A1 boiler incentive is running out though and will not be available much longer. If your local plumber is part of the scheme they may still be able to get a voucher.
Don't be frightened of condensing boilers - but do look at the better end of the market. Get lots of estimates from good, longstanding, reliable firms then make your decision. If you don't know who to call, ring a couple of manufacturers such as Vaillant, Viessman, Worcester etc and ask their rep for a local good installer.