I purchased a pair of Torin T43004 jack stands recently - without doing much research beforehand. After buying them, I realized that it would have been better to have purchased the same stands, but modified to enable use of jack stand blocks. (I saw an ad in the Roundel on this - from a company called Reverse Logic.)
I reached out to Reverse Logic via email and received a quick reply back from them - a gentleman named Fred Gwinn.
Fred was really helpful - and since my Torin stands were new, he offered to exchange the inner tubes with similar ones that had been drilled to accept jack stand blocks for a nominal fee and the cost of the new jack stand blocks manufactured by Reverse Logic.
Anyway, in a matter of a few days, I had the new inner tubes and jack stand blocks. I also purchased a Lug Bolt Guide tool - very handy when reinstalling my 19" CSL wheels on the car.
In my experience, it's pretty rare to find a company that manufacturers products like these that is so responsive and easy to deal with.
I highly recommend Reverse Logic- and Fred Gwinn. You can see their stuff at:
www.ReverseLogic.us