My thanks to all the responders. I'm encouraged by Vladimir's advice regarding writes. I've been thinking about wear leveling, and based on how much disk space I really need to run the relatively static firewall VM images, there will be a *lot* of unassigned spare cells in the flash, so writes shouldn't matter much after all. I'll mount the filesystems with the 'noatime' option since that info isn't needed, and put /tmp and /var/tmp in tmpfs. There are also other tricks mounting ext4 partitions that significantly reduce writes. So, it would appear this is a no-brainer. I was also made aware of the 'vm.swappiness' kernel parameter, and since swapping is very unlikely to ever happen, I can safely set this to zero. On a side note, I'm really surprised that constant same-region reads can cause wear. That's something I would never have thought of. The plan is to use Intel 520-series SSDs in software RAID-1. A high-quality power supply and a motherboard with all-solid capacitors would also raise reliability. I usually underclock CPU chips a bit, and use really good coolers (such as Noctua), so it all adds up. With any luck the box would run pretty well forever :-) Thanks all! Chuck