I've had my existing pair switched between the 2 cabinet types.
My line on the ECI DSLAM could not hold on to fastpath.
With Interleaving on ECI my sync is 36Mb.
My pair was then swapped to the new Huawei DSLAM.
Initially with interleaving the downstream sync was almost identical.
With G.INP, and a 3dB noise margin I'm now synced at 50.5Mb.
So I'm not surprised that Huawei lines (even though longer in general) outperform ECI lines.