Indeed FWIW here's one player's updated Thiele C90 musings. The cab design definitely has it's frequency characteristics and was done originally with the EVM in mind. With the C90 it's got a focused frequency spectrum very different then the WB C90 1x12 cab, which was boomy and loose in low freqs and spread out in the upper freqs.
So mucked around with it as the sole 1x12 with the IIC+, V:90, Stiletto, LSS and Badlander. Then paired it with other cabs. A few notable points...
First as an extension cab it is a real tone shaper, it accentuates the C90 characterisics low & low mids and pushes the upper end in a narrow freq range. It stood out paired with the Stiletto Scumback (greenback like) Combo, added that top end sparkle the Scumback was a bit lacking in, especially with the Ch 1 Tite Clean setting. Also gave the bottom end a bit more defintion and EQ response.
As a sole 1x12 with the LSS, hands down it is the best cab I have found for that amp and have been thru a few. The amp can sound like a blanket was thrown over it and prone to get lost in a live mix. But this was a difference maker. No problem cutting thru a live mix and it's characterisics matched really well with what the LSS does. Chimey cleans and smooth Ch 2 mids with a bit of brightness layered.
With the rest of the amp lot as a sole 1x12 it was a "can't go wrong" solution, the one exception was the V:90 which had a very annoying upper freq content that was pronounced.
So now onto swapping the EVM into it and having another "speaker geek' roundtable