>Isn't the data written to any logically encrypted partition always fully encrypted, even if the system hibernates? Any chance of security leak?
>Would the levels of wear differ at all during use after encryption?
>Comments on full disk encryption?
On a RAID 0 system of two SSD, integrated RAID controller on motherboard with motherboard integrated TRIM.
The data written the disk is encrypted in memory first, on the fly, and then written to disk, it never appears at all on the disk as plain text.
System hibernation is a problem, while the system is on and encrypted partitions are mounted the keys to encrypt and decrypt the hard drive are stored in memory and with hibernation the contents of memory are written to the disk. Full disk encryption of the OS drive solves this problem so make sure you're encrypting the OS drive when mounting other partitions.
Wear levels are the same encrypted as non encrypted, the only additional wear is a one time pass on the drive to do initial encryption. Truecrypt encrypts the free space in partitions so even empty drives go through an initial full drive write, no big deal.
Additional comments:
1) RAID 0 is built for speed only and not redundancy, in fact it has a greater chance of failure because fragging one drive breaks the entire array, make sure to take precautions for redundancy, RAID 0+1 is a good option for speed but reuqires 2x more drives.
2) Performance - With any full disk encryption the speed at which you can read/write may be limited by the CPU doing the encryption/decryption, truecrypt comes with a benchmark tool that allows you to see the max read/write speeds based on your hardware and encryption type.
Normally with a decent CPU (high end Intel) and slowish drives (single spindle) and fast encryption (AES) it's not a problem. However you plan on running RAID 0 for speed on faster SSD's, you have a potentially HUGE data transfer per second so it's worth benchmarking the max throughput of the drives non-encrypted and then benchmarking your CPU with Truecrypt and comparing the data rates.
Even if the CPU isn't a bottleneck for reading/writing data it's likely the CPU would be under significant load during read/writes and that could be problematic if the box has other roles that require CPU time.
It's also worth noting the newer Intel CPUs have hardware based AES acceleration which truecrypt supports which MASSIVELY boosts the speed at which the CPU can encrypt/decrypt the data (from 100's of MB/sec to several GB/sec), this would be a good route to go to keep performance of the array nice and fast if you're struggling.