Here are some factors to consider when getting an adjustable bed.
How fast you want it to be able to change its position
You'll need to think about how quickly you'd like to be able to change the bed's position, as some adjustable beds move faster than others. If you need the support of the elevated bed to get you up in the mornings (if, for example, you have a back injury that makes pulling yourself into an upright position hard), and you need to get up quickly so you can get ready for work, then it would be sensible to pick an adjustable bed which can be moved from a flat position into an elevated one in seconds. You might also find a fast-moving adjustable bed useful if you're impatient and would be frustrated if you had to wait several minutes for it to get into the right position every morning.
Conversely, if you get dizzy easily or if you are not a morning person and like to arise in a gentle manner, then a bed that moves too quickly might make you feel unwell or frazzled. A slow-moving adjustable bed could also be the right choice if you have back pain which is sometimes triggered by you moving your spine too rapidly.
How much noise the bed makes
Adjustable beds don't make a huge amount of noise. However, most of them make a whirring sound when they're moving, and the loudness of this noise varies depending on the model. It's important to bear this in mind when buying this item. If for example, you have a roommate or if your home's walls are thin, getting a bed that makes a loud whirring noise every time you adjust it might start to bother the people you live with, especially if you make adjustments to the bed late at night. In these situations, splurging on an extra-quiet adjustable bed might be worthwhile, as you could change its position at any time, without worrying that this would irritate the other householders.
Conversely, if you'll only be elevating the bed in the mornings when you're getting up, it might actually be helpful to have one that makes a slightly louder whirring noise, as this could stir you on those occasions when you start to doze off as the bed lifts upward. This would then ensure that you stay awake instead of falling asleep again.