Torque Tanks & Concept 2 Bike Erg

I somehow became interested in Torque Tanks.  Recently there have been two M4 listed and both sold within a week.  One at a list of $900 (new in box) and another for $800.  The M4 is a premium item that retails for $1600 and is huge.  Hard to image having one in a home gym.

The M1 is a newer model that has been favorably reviewed by Coop and Joe Gray.  That one lists for $824 (with free shipping) and I would love to snag one in the secondary market for $500.

The Concept 2 Bike Erg is another premium piece that I have recently seen sell at the same price point of $800 and $900.  These things retail for $1100 plus shipping.