I always recommend solid foam mattresses to customers who require a shallow mattress.Buying a sprung mattress less than 7 inches deep is really buying a trip to your local tip in 6 months time. Solid foam mattresses have really come on in the last couple of years.Respected makers such as "Relaxsan" have remained at the cutting edge of solid foam technology by using different layers of reflex foam to ensure the mattress keeps its shape and remains cool and germ free to sleep on. Ideal for children as they are on the whole anti-allergenic and virtually indestructable.
 However sprung mattresses remain the most popular in this country.I think this is due to us not liking change or maybe we just enjoy the bouncy feeling when we sit on the end of a bed in a showroom ( Im still amazed that some customers choose their mattress based on sitting on the end of a bed for 30 seconds !)
 I have tried to convince customers over the years that a solid foam mattress will far outlast a sprung mattress and offer the same level of support and comfort, indeed manufacturers offer a far longer warranty period, but to no avail.I guess its like having carpet around our toilets, we`ll never change !
 Its really down to your personal preference at the end of the day as they both provide great support and comfort.
 I myself sleep on a sprung memory foam but will probably change next time around for a solid foam/memory foam.Why you might ask ? well I have been really impressed of late by makers like "Healthbeds" , "Concept" and "Relaxsan" and the quality and comfort levels which they have taken to new level, coupled with the anti-allergenic properties of all these mattresses I believe they represent the best of UK manufactured mattresses.