The question is a shopping question because it asks, and I quote:
Does anyone know of any RAID cards which can be configured to check
the parity of a redundant array every time data is read, and verify
all writes with a read to ensure that the data on a single disk didnt
As well as:
I am specifically looking for a controller which can verify on write
and check pairty on read.
There is a history of not allowing subjective shopping questions on StackExchange (a rule more faithfully followed on some StackExchange sites than others). Yes, there can be a method of asking a shopping-style question that is acceptable. To quote that blog post:
However, there is a way to ask these questions that avoids the
inherent problems with shopping recommendations. For example, let’s
say you wanted — as I did — to buy a point-and-shoot camera that takes
good low light photos. [...]
Q: What’s the best low light point-and-shoot camera?
Q: How do I tell which point-and-shoot cameras take good low light photos?
The former question provides the path of least resistance: a laundry
list of products I can buy without thinking about it too much. But
that answer will only be valid for a year at best. The latter question
may take some thinking, but its answer will be valid forever … or at
least until camera technology somehow shifts beyond lenses and sensors
as we know them today.
However, the proper way to ask a shopping question is to not ask it like an explicit shopping question, but rather as a question seeking to understand how you determine what you need.
Your question is not seeking to answer something along the lines of "How can I determine the necessary features in a storage card when my goals are thus-and-such?" Your question was explicitly seeking specific RAID cards, not methods to discover the proper technology to solve your problems.
The blog post says the former is unacceptable because it "provides the
path of least resistance: a laundry list of products I can buy without
thinking about it too much". The features I listed are very obscure
and were could not qualify has having a laundry list of answers. The
very fact that no one was able of offering single RAID controller
which had those features further proves my point.
No matter how exacting and obscure the list of requirements is and even if there is only one single possible product that could fit the bill in the entire world, it's still shopping and off topic. A laundry list is still a laundry list even if only one shirt got starched.
If the most natural answer to a question is "Oh yeah, you need Wingding 4000 in 3D!" it's a bad question and off topic. If the most natural answer is "Here's how you evaluate this technology to narrow your eventual list down" then it's on topic.