The test kits are different so not directly comparable. The "bang for your buck" is from the larger volume of reagents in the TF-100 kit, especially for the FAS-DPD chlorine test. However, this comparison was before someone found the inexpensive Amato Industries pricing where one could get the K-2006 plus extra reagents and come out fairly comparable price-wise though these things aren't static since the TF-100 has changed over time, increasing volume of certain reagents.

I have both test kits and like certain aspects of each. I do prefer the larger pH block of the K-2006 and once in a while I'll use the acid demand test. I prefer the wider-range and larger and separate view tube for the CYA test in the TF-100 (also available separately from Taylor, but not cheap).