Simba CustomFlex Pillow Review
An adjustable pillow, and since I recommend adjustability constantly it is worth being precise about what the word covers.
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Verdict
An adjustable pillow, and since I recommend adjustability constantly it is worth being precise about what the word covers. There are three different mechanisms sold as adjustable and they are not equally good at the thing that matters.
Buy it if
You do not know what height suits you, which is most people, and you want to be able to change it repeatedly.
Avoid it if
You already know your loft and want the cheapest pillow at that height.
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| Specification | Detail |
|---|---|
| Type | Adjustable pillow |
| Three kinds of adjustability | Removable fill, removable layers, and reversible or zoned surfaces |
| What decides a pillow | Height, which depends on position, shoulder width and mattress firmness |
| Setting it | The ten minute test, described below |
| Reset it | When you change mattress, which most people never think to do |
The scores
Adjustability done properly, which is the right answer for a product nobody can spec in advance.
More than a fixed pillow, less than buying three fixed pillows.
Keeps most of its height, though not indefinitely.
Good once set correctly, which is a real condition.
Depends on the fill. Loose fills breathe better than solid foam.
The reason to buy. Height is the variable and this one moves it.
Check which parts wash. Fills usually do not.
Three things called adjustable, and they are not the same
| Mechanism | How it adjusts | Good for |
|---|---|---|
| Removable fill | Take handfuls of fill out or add them back | Fine control in small increments. The most precise of the three. |
| Removable layers | Unzip and take out a whole foam layer | Coarse control in two or three steps. Simple, and you may land between settings. |
| Reversible or zoned surfaces | Flip the pillow for a different feel | Feel rather than height. This is the one to be careful with. |
Only the first two adjust height. A pillow that is firmer on one side and softer on the other is adjusting feel, which is a real preference and not the variable that decides whether your neck is in line with your spine.
So when a listing says adjustable, ask which. If the answer is that it flips over, it is not solving the problem you bought it for.
Set it properly, because most people never do
The commonest waste of an adjustable pillow is leaving it exactly as it arrived.
Start where your position suggests. Side sleepers high, back sleepers medium, front sleepers as low as it will go.
Run the ten minute test. Lie in the position you actually sleep in for ten minutes so the pillow settles, then have someone look at you from behind. Your neck should be a straight continuation of your spine: tipped up means too high, dropped means too low.
Change one increment at a time and give it a week. Necks adapt slowly and the first two nights after any change are not representative.
Reset it when you change mattress. A softer mattress lets your shoulder sink further, so you need less pillow height. This is the most common reason a pillow that worked for years suddenly does not, and almost nobody connects the two.
And change the pillowcase
Whatever you set the pillow to, you are sleeping on the pillowcase.
A cheap polyester case is an insulating layer between your face and the pillow, and it holds moisture against the skin, which is what people actually experience as sleeping hot.
Cotton percale or lyocell costs a fraction of the pillow and does more for how cool it feels than the choice between pillow types. It is the highest ratio of effect to cost in bedding and almost nobody does it.
A correction worth making
Commonly repeated, and wrong
Adjustable is used for three different mechanisms and only two of them adjust the thing that matters. Removable fill and removable layers change the pillow's height, which is what determines whether the neck continues the line of the spine. A reversible pillow with a firmer and a softer side changes feel at a fixed height, which is a preference rather than a fit. A listing that says adjustable without saying which is describing two very different products.
Should you buy it?
Yes, and it is the right kind of pillow for a product nobody can specify in advance. Set it with the ten minute test rather than leaving it as it arrived.
Reset it if you change mattress, and change the pillowcase, which does more for how cool a pillow feels than the pillow does.
Questions people ask
What does adjustable mean on a pillow?
Three different things. Removable fill and removable layers change height, which decides whether your neck continues the line of your spine. A reversible pillow with a firmer and softer side changes feel at a fixed height, which is a preference rather than a fit.
How do I set an adjustable pillow?
Start where your position suggests, then lie in that position for ten minutes and have someone look at you from behind. Change one increment at a time and give each change a week, because necks adapt slowly.
When should I readjust my pillow?
When you change mattress. A softer mattress lets your shoulder sink further, so you need less pillow height. That is the most common reason a pillow that worked for years suddenly does not.