Our old expensive-at-the-time John Lewis mattress has done very well on a sprung slatted base (no mention then of needing leveling but we see the logic) but is now a bit hard for our aging bones despite having two toppers. We chose firm as the advice 20 years ago seemed to lean towards that being best for us even though we were and are not particularly heavy (both 5' 8", one at 10 stone 4, the other 11 stone 5, though aiming to be back under 11 stone soon!). We tried and liked a Regal Superb medium that was on a divan base, but we will be keeping our slatted base so please can you advise us which mattress you think would suit us and our base best? My husband has shoulder pain on and off and is the lighter of the two of us so the softer feel of the Regal Superb compared to our current mattress appealed to him especially. We can spend up to about £1,700-£1,800. Many thanks for your amazingly detailed website; I've been looking at it for months now.