Hello Heyali and thank you so much for the inquiry! I don't normally recommend a latex and coil hybrid for folks over 230 pounds due to a lack of support from the coils. As such, I would definitely recommend our 13" organic latex mattress with the following configuration:
Layer 1: Firm SPLIT Soft 100% Natural Talalay
Layer 2: Firm SPLIT Medium 100% Natural Dunlop (GOLS)
Layer 3: Extra Firm SPLIT Firm 100% Natural Dunlop (GOLS)
Layer 4: Extra Firm SPLIT Extra Firm 100% Natural Dunlop (GOLS)
Please don't let the terms "firm" fool you, the firmer side will feel more like a soft or medium mattress to someone at 325 pounds. The top Talalay layer should provide all the contour and pressure relief needed to avoid any pressure point issues and will add secondary support to the mattress. Secondary support is needed to fill in the gaps between your body and the mattress – back sleepers normally need secondary support to fill in the gaps between the small of their back and the mattress; side sleepers normally need secondary support to fill in the gaps between their mid-section and the mattress. If these parts of a person’s body aren’t supported by the mattress, their muscles will work throughout the night to hold these parts of the body up, and by the time they wake up they’ve got back pain. So the top 3” of Talalay latex will provide contour, pressure relief, and secondary support. The remaining Dunlop layers should provide all the support needed to maintain proper spinal alignment and avoid back pain. Please keep in mind that our initial recommendations have a 90% success rate (we only have a 10% layer exchange rate and a 3%-4% return rate) so there's a 90% chance that the above recommendation works perfectly for you.