Non-Cross Focus Points 5D3 vs 5D2

Coming from my Mk2's to new acquired Mk3's I'm loving the new focusing system.

Initially I've set it up just to work with the 51 cross-points but the non-cross points don't seem too shabby...

I was never happy with outside focus points on my Mk2 (particularly in low light,) and so used the centre point every time - but I'm wondering if the Mk3 has improved accuracy over the Mk2 on it's non-cross points.

Thoughts or info anyone...?

LEE