Thinking about getting a Samsung 830

I'm very tempted to get a 256 GB Samsung 830 to replace a 160 GB X-25M that's over 90% full, but have a couple questions:

1) What is the formatted capacity of the 256 GB Samsung 830?
2) How fast is sequential read/write? I rely on a program that dumps several gigabytes of RAM to disk when "saving" and reads it back into RAM when "loading", so sequential is more important to me than random. I'm actually quite tempted by the Plextor M5 and the new 840 Pro as a result...
3) How much does performance suffer as the 830 gets filled up? The X-25M dropped from about 90 MB/s sequential write back when I only had about 100 GB of data to about 60 MB/s today when it's nearly full, which is slower than an HDD. And thanks to continuing software bloat, I'm sure I'll eventually be in this siutuation again a few years down the line

 

With the 256GB Samsung 830 you won't have to wait a few years to get to this degraded state:

See:
AnandTech - The Samsung SSD 830 Review



For the 256GB capacity, the Intel 520 Series is still the most responsive drive (overall, sustained...).

The Samsung 840 Pro is even worse (hitting a new low of 20MB/s...):

See:
AnandTech - Samsung SSD 840 Pro (256GB) Review

As to the formatted capacity? I'm pretty sure it's right around 238GB in Windows w/NTFS.

Your best bet for sustained SSD performance that gets you close to what we're promised with SSD's: buy double the capacity you require and partition the drive to use only half (from day one of ownership). This is what I've been doing for almost a year and don't see the 'new gen' SSD's performing any better in this regard.

Paying SSD prices and getting HDD performance is not what I signed up for, but I'd rather pay ~twice the price and get the sustained and high performance I expect than save a few hundred dollars (over the life of a system) and get up to 3x less performance (depending on what we're measuring in 'real world use').

Hope this helps.

 

I stopped reading Anandtech's SSD reviews a long time ago - quite frankly, their testing methodology sucks. Their TRIM testing in particular is a joke as the format-to-TRIM approach Anandtech uses completely ignores differences in how (aggressively) different SSD controllers handle a TRIM command from the OS.

As for the Intel 520, the low performance with incompressible data concerns me.

 

If you format a whole drive with a Windows 7 SP1 command it tells the SSD that all blocks are free - there is no waiting for anything to happen: it simply writes the next data as if it was a new drive.

As for not agreeing with the testing methodology - sure, I don't agree with everything out there too, but when I see results from the 2001 notebook HDD era (20MB/s) - I just know to run, not walk from that product.

As mentioned before: if you keep a lot of capacity unused (via partitioning, not simply having 'free space' on the SSD) then the lowest performance of an SSD is still much better than a HDD. A pricey way to achieve performance, but if this is work related (as it is with me...) then the cost doesn't matter - and the gain in performance is easily worth it (to me).