Having just upgraded my netbook from HD to SSD, the difference isn't as much as I hoped.
Noise: the silence is a little disconcerting. The click and hum of a hard disk is almost reassuring that a computer is on, leaving the job to the cooling fan. I'm sure I'll welcome this in the long term but for now I'm still in the getting used to it stage.
Power consumption: Might actually be slightly higher than the disk I took out. In a desktop scenario, it could show more improvement over 3.5 inch drives, but doesn't seem that different compared to 2.5 inch drives.
Capacity value: of course this is the biggest weakness for now. For HALF the cost of the 40 GB SSD, I could have got a 500GB model in the 2.5 inch form factor. Going up in physical size, 2TB in 3.5 inch format could be got for the same price as the SSD. You will not be picking a SSD for capacity!
Performance: While the benchmarks confirm it is performing as expected, in practical use I haven't felt it. Maybe the applications I'm using are light enough the disk was never a significant bottleneck after all.
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