Very few installers suggest this but esp for a larger house a combi and cylinder can be very effective- cylinder near the bathroom(s) so no long wait for hot to come through, kitchen tap on the combi so same plus avoids a fair bit of the kitchen/shower hot water interference. Unvented cylinders (if mains pressure/flow are up to it) are good but there's an annual maintenance overhead to consider.
Boilers- my next one will be Intergas, i like the simplicity (no diverter valves or similar bits to fail). TBH most now come with 7+ years warranty (as long as they're serviced)
Boilers- my next one will be Intergas, i like the simplicity (no diverter valves or similar bits to fail). TBH most now come with 7+ years warranty (as long as they're serviced)