I'm a mattress tester and this Zinus queen bed is the only deal you need to know about for Prime Day — it's cushioned comfort for side sleepers with arm ache

(Image credit: Zinus)

I've been waiting for the Prime Day sales to bring discounts on mattresses but so far the deals are (whisper it)... disappointing. I was ready to write the sale off altogether until I stumbled across the Zinus Green Tea Mattress, now just $162 for a queen at Amazon, and now I'm glad I didn't sleep on these offers.I reviewed a version of this Zinus bed and I rate it among the best mattresses we've tested when it comes to sheet value for money. I was most impressed by its pressure relief for side sleepers — within minutes of lying on the bed it was as if my shoulders and hips were being cradled by a marshmallow.So perhaps I was a little hasty to write off the Amazon Prime Day mattress sales. This deal certainly proves there are great offers to be had, although I'll be keeping an eye out more offers in the 4th of July mattress sales. If it's better sleep for less you're after, shop this Zinus mattress deal now.What the Zinus Green Tea Memory Foam is the best bargain mattress to buy this Prime DayI haven't tested this exact model but I did sleep on an older version of the Zinus 10-inch Green Tea for several weeks. You'll find all the details in my Zinus Green Tea Memory Foam Mattress review but with Prime Day nearly over, here are the headline...It cushions shoulder and hip painThe stand-out feature of the Zinus Green Tea Memory Foam mattress is its body contouring. As soon as my shoulder hit the bed I could feel the foams moving around me to cushion the joint and prevent sore spots from building up. It's this that earned the Zinus a place in our guide to the best mattresses for side sleepers.Most side sleepers will know the pain of sleeping on a bed without sufficient cushioning. Think numb arms, tinging hips and aching knees. But because the Zinus hugs those key touch points to evenly distribute weight, you can avoid sore morning.Co-sleepers won't feel their restless partnerThe cushioned foam of the Zinus Green Tea means it also delivers excellent motion isolation, which is the ability to absorb excess movement. When your partner moves around, the thick foams will deaden the motion before it reaches you (it can't do anything about the snoring, though.)I sleep alone but I tested this by asking people to hop onto the bed while I had a quick lie down (yes, a strange request.) In some cases they were able to get on and off the mattress without me noticing, so expect minimal disruption from your partner's 3 a.m. wake ups.