I found such comments to change with each saleperson. Their job is to sell you what they have. It is a fact that what they have to sell us is what they will talk up.
But when upgrading you have to think about this with care. You don't want to replace a 5 Watt hard drive with one that draws 10 Watts. Why this is should be easy to figure out.
I've decided to upgrade my current hard drive and one of the aspects I'd been told to consider was the rotational speed of the drive, ie. 7200 rpm is better than 5400.
I went into a shop and the salesperson showed me a number of hdd's and when I asked for one with a speed of 7200, he said they typically sold and recommended 5400 for laptops, as "7200s are less reliable with notebooks" and said this was due to them being moved around, while a 7200 rotational speed is fine for desktops as they're fixed. In essence, the higher speed was fine when the box wasn't being moved around.
Is this really the case? As my days of Morris dancing, while using a laptop are behind me, is this advice nonsense or sense worth considering?