Old tin ear here had it done to my workhorse, EBMM Morse #1, and it is all good. Thirds (both m3 and M3) in open voicings (like EJ's Trademark) are such a bitch on our instrument with our even tempered tuning system. I felt this made it a little better. Thinking about investing in a Tyler, and will look into the BF on it too. We are playing great amps that can dish out the odd and even harmonics in a pleasing manner, so I guess we owe it to ourselves to be in tune. If you are playing music that oozes 3rds (and their inversion - 6ths) or 7ths (and their inversion - 2nds as in sus2 and 9th chords), it will be very noticeable. If you are doing more the power metal 5th thing, it will be less noticeable as 5ths are in tune just fine on a standard guitar setup.