very nice!
are you able to control the steam heat precicely? if so great. Set it to your mash temp and leave it...that should keep the whole mash at a constant temp.
I used to have major issues with maintaining mash temps, though the beer was still great, just not consistently the same.
I've since built a herms coil that sits in my hot liquor tank and I recirculate wort through the coil from the mash tun, back into the mash tun. the water in the hot liquor tank is at a constant temp and maintains the mash quite precicely.
Not sure how much you know about that type of mash heating but it's call HERMS (heat exchange recirculation mash system, or heat exchange recirculation infusion mash system).