I've just picked up some 4.5Ah D cells in Lidl for ?2.99 a pair. Maplin own brand are 3.0Ah for ?6.49 a pair. Lidl ones work very well and are heavier so no reason not the believe the extra capacity, which is why I got some more. Maplin 2.8Ah D cells are ?9.99 a pair (looks like discontinued) and probably just AA cells in a D cover (most D or C batteries of similar capacity for most makes are supposed to be just AA's in a bigger coat. OK Lidl are ephemeral when it comes to availability, but Amazon has also been invented, with lower overheads than high street stores and their daft rent levels. Makes competition harder.