I have no doubt that an SSD is great, as I have heard many good things about them. I have never had the chance to use one though. The only disadvantages I've heard about is that you cannot defrag an SSD because it's an electronic device. I also know that SSD's typically have less storage space than an HDD, but I have seen SSDs go up to 250 GB which is way more than I'd ever need.
Solid states drives are flash drives basically. There are no moving parts. Since they work on flash cells, reads/writes are limited and each time you overwrite a block, you slowly degrade the capacity and capability of that cell. A full write cycle, however, is not complete until you overwrite the full drive one full time. And keep in mind that consumer drives are rated for tens of thousands of write cycles. Even though their time is limited, it's not as short as you would expect.
I have no doubt that SSDs are the future though and I'm sure that the storage space will improve as time goes on...but I do wonder about the inability to defrag. Does anyone know if that will really effect the performance since it is a SSD? I honestly don't know, so that's why I'm asking.
Because of the way SSDs work, defragging is very bad for them since that uses a lot of write cycles. Reading is fine, it's writing that becomes an issue. The more you unnecessarily write to a flash cell, the quicker it dies and subsequently, the quicker the entire drive dies. The only application for consumer drives really is being a boot drive at this time. Unless you can afford an enterprise class SSD, you're stuck with a boot drive. That's what I currently use for my OS drive and it's incredible. It is
lightning fast.
You, also, cannot treat an SSD like a traditional hard drive. You'll burn it out a lot faster if you do. There are plenty of optimization guides available on the web. You say 250GB is enough? A 250GB will run around $300 to $400, which is far from cost effective. Snag a 32/64GB SSD, run Windows 7 and core apps, then use traditional drives for games and storage. That's currently what I do and it's good times.
You don't really need to defrag so much with an SSD, considering it's instant-access. It's basically a glorified flash drive, and when was the last time you had to defrag one of those?
It's not so much the instant access, but the way flash cells work. See above.
SSDs currently are lower on storage, higher on speed and consequently higher on price.
The performance boost is amazing. Besides, they are dropping in price fairly steadily and have been doing so for the last year and a half. In 2009, a 60GB OCZ Vertex was around $240; now you can buy a better Agility 2 or Vertex 2 for less than half of that price. Still not ideal, but for the novelty and performance boost, it's well worth the cost. I can vouch for that for sure.