Origins Pocket 1500 vs Silentnight Stratus Premier Naturals 2600

Thank-you for an incredibly informative site! After quite a bit of research, I have narrowed my choices to an Origins Pocket 1500 (2000 spring double version for 480), or the silentnight stratus premier naturals 2600 on amazon for 500. Could anyone kindly help me compare the two as I am finding this comparison quite challenging to make, they have similar pocket spring counts but the silentnight appears to have the advantage of natural upholstery. I weight 95kg and am looking for a medium-firm feel.