I have listened to a special edition of the CAT ultimate MK2 for 11 years .
I swapped it 5 months ago for a young Legend pre amp .
The most obvious difference is refinement , you hear more detail .
To my surprise they sound very different in the Bass region , the legend sounds slightly leaner , i reckon it is actually slightly more balanced / neutral , but it needs time to get used to
Both are great natural sounding pre amps , with total control over the freq range