SSDs are always expensive, that's something we can now take for granted. Sometimes you get the odd bargain cropping up, such as Kingston's li'l 40GB lightening rod, the SSD Now V-series, but by and large you're going to be forking out a hell of a lot of cash for the privilege of no moving parts.

The usual trade-off though has been in terms of speed; a good SSD can outperform even the fastest of HDDs. So is Imation's M-Class a good SSD?

Sadly for them, no. I'll get the positive out of the way first, as that'll take less time; it's been created in a 3.5-inch form factor so you can fit it in any standard HDD bay. Good-o, though increasingly irrelevant given the brackets that are now cropping up for the 2.5-inch drives.

Now the negatives. It's slow in modern SSD terms and falls well short of the promised 150MB/s and 90MB/s read/write speeds. It's also got rather low random 4K writes, simulating the constant, small writes that occur during normal drive operation.

Indeed, it takes quite something to make the Barracuda XT we've looked at seem like a bargain. Even when plugged into a SATA 3GB/s interface it's still just as quick as this drive, and it's 2TB of storage towers over this 128GB offering.

And it's cheaper. So if you want a quick SSD for bootdrive shenanigans then the far cheaper Kingston drive is a good, speedier bet, but if you're happy to spend £250 on a drive with this sort of performance then the Barracuda XT or WD's Caviar Black is for you.

But whatever happens, steer clear of the M-Class.

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