I have an
M7060, 1000hrs, 8yrs, no issues with the emission system.
It regens more with light work, and colder temps of winter. Ive ran this machine around at both low rpms and higher rpms and it does not change the fuel burn enough to notice. There is a fuel burn display on the dash to watch.
The machine feels happier to me at a higher rpm, like 22-2300.
Amount of load on the engine effects the fuel burn and is very noticable.
My father has a 40ish hp Branson with a DOC, not a dpf. He likes to idle around. His DOC (no computers involved, its basically a fancy cataylic converter) will plug up, the 2 sensors involved are simply pressure switches that trigger a light on the dash, same symbol as the kubota regen...... he then needs to drive around, under load, to make enough exhaust heat so the DOC filter will self clean.
I had a DPF system on a VW TDI. It never caused me issues (many have though) but since its been on the shelf, its been very problem free. That option exists for most of our tractors too, in certian countries at least. That car got me 63mpg on the last tank of fuel, running the speed limit.