Pros: Delta fans are great, if you know what you're getting yourself into. These are not made for home use, at least for anyone who values their sanity. You will find Delta brand fans in many datacenter products such as servers, routers, switches, etc. These things are built to last, and blow some serious air around. However, they are built for such environments - noise is not a consideration.

Cons: Expensive - These are hard to come by at retail, and when they are found they are rather expensive. However, keep in mind these fans will likely quite literally last you a lifetime through many projects, vs. cheap much less capable sleeve bearing fans. Ouchies - Not really a con, but seriously buy a fan guard if these are somewhere fingers can get into them. You really don't want to experience getting whacked, I'd imagine it could break a child's fingers rather easily.

Overall Review: High-CFM Delta fans are a must-have for any workbench. - computers or electronics. When you absolutely need it cooled, these are what you should be reaching for.

Pros: These cards work well. Very well supported open source drivers, and well maintained by Intel. They generally Just Work.

Cons: Artificially firmware locked to Intel optics. Absolutely unforgivable in a datacenter environment. Want to migrate that Twinax connected server across the room and need to swap to LR optics? You're out of luck and you better hope the entire ops team realizes this before scheduling anything. Lord help you if you find you're out of the right length twinax and need to get a server up quickly during an emergency! Latest Linux drivers have a module load parameter you can use to disable this ridiculous firmware check. However, if you run these cards w/ a statically compiled kernel you must modify the driver source to get around the vendor lock.

Overall Review: Great performance, well supported, but absolutely inexcusable artificial vendor-lock for optics. Look at picking up the Supermicro branded versions of these cards (no firmware lock), or looking elsewhere at Myrinet for a company that makes extremely well performing cards that don't play games that make operations hell. If you run Linux and can live with using loadable modules, you can also disable this check. No Intel, I am not going to stock a bin of optics just for you in every location.