In the eighties I bought my first wife a Dacor 950 Pacer XL. Outstanding regulator. Their products were great until they got on the plastic bandwagon.
As far as Mares, 4 years ago I bought an MR12 DFC/Proton for my wife. Out of the box breathed like a 1st generation Air2. Overhauled the Proton, still not suitable as anything but a Pony/Octo reg but the DFC first stage is great and now bears my G250 2nd stage as a great combination. IP is quite stable at all tank pressures on the Mares DFC and only drops about 5 PSI with the G250 in full free flow. All of my Scubapro first stages will drop to about 110 just inhaling.
Did some testing with an IP gauge and found my SP Mk10 is not well balanced at all (my Mk5 and Mk 7's put it to shame, and this was immediatley after being "professionally" serviced at my local SP dealer)
SP's own specs put the IP at 125-145 at 300-3000 which is about the same as an old 1963 Nemrod unbalanced Snark 2 in my collection, granted the Mk10 has higher flow rates. Another reg that did surprisingly well in my simple tests (Observing intermediate pressure on tanks at 3000 and 300 PSI, static and while free flowing) was a 1981 Sherwood Magnum first stage I picked up in trade years ago.
