my sincere suggestions are:

1. buy those brands really long history and reputable, eg vono, dreamland those

2. be very sure on what you need, like my case, i used to have backpain and shoulder pain like you everyday, i changed to coconut fibre mattress, one of the best decisions i ever made in my life so far.

Serta expensive bro, please choose between this la

nosda mattress nosda.com.my
sonno .sleepsonno.com/
joeymattress

I was thinking to get a new mattress and recently there is few of the mattress brand is keep on popping up in my screen. I have some back and shoulder pain and thinking to choose 1 among the few brands.

NOSDA
sonno mattress
joey
origin

Here is what I got.
After looking in their website, from my point of view,
- joey is the cheapest but the material inside is just normal foam even they are using some fancy word like J foam. 
- origin mattress website is kinda misleading by putting a lot of featuring logo, such as USA today, NBC news, FOX and Latex mattress buyer guides. Most of it cannot be find in the google, so I think they are just putting there and it's fake. So I am a bit concern about their business ethic. Please share your experience here if you have bought any of their product.
- sonno, the price, quality and brand is kinda well know and I saw their mattress showcase in some of the shopping mall. It's kinda comfortable but I saw their competitor Nosda mattress, they are offering better material with Coolsilk cover and more layers. So I am a bit confuse which to choose.
- Nosda, so far it's the most value for money after comparing 4 of the brands, they offer thicker layer, better material and more feature, like activated charcoal latex and coolsilk cover and backcare, which didn't mention in their competitors. The price is slightly more higher like 5-10% and quite similar with Sonno. They claimed to be the most cooling mattress in Malaysia, is there anyone try it before

So I am kinda struggle and donno which to choose, they have it in 2 different model, a budget version and their flagship model.

i don't see brand, normally i would go for pocketed spring instead of pocket spring. 2nd, the base is hard, then top layer is a thin/ moderate thickness of soft cotton/ cushion depends on your comfortable. at least when you sleep, it wont be so soft until you sink in or hard until sleep till back pain. i bought my king size abour RM2.7k iinm.