I have a FloBed Latex Queen Split Mattress with a 1' latex topper. I can't notice any split in the middle since the latex pieces fit tightly in the zippered sturdy mattress cover and the topper has no split in the middle I love my bed so much. it did take a while getting the latex cores to be just right for my needs but it was worth it and FloBeds allowed me to make several exchanges. Amazingly, I like a very firm bed. The 2' topper that came with the bed was too soft for me. I have my 1' soft topper (that fits inside the zippered cover that looks just like a real mattress when zippered up) is over a 37 ILD Extra Firm Latex Core over a 37 ILD Extra Firm Latex Core over a 46 Super Firm Latex Core over a slat box with 10' legs to allow room to store things under my bed. The mattress is about 11' thick with the 1' topper.

My other size of the bed has the 1' latex topper over a 36 ILD over a 44 ILD over a 39 ILD. ILD is a way to measure firmness.

I know a couple where one partner has all medium latex cores and the other has a mixture of extra firm and firm but only have two layers of latex so are closer to the slat box so that firms up the bed even more.

Here is a link that might be useful: FloBeds link to the latex bed I bought