You'll be completely fine then. Refresh rate matters only with high rates of fire, and if you've got a solenoid then they require far less air so you'll be golden. It would appear that whilst this reg is an upgrade over the Firebase, it's mostly aimed at some of the mechanical pneumatic users (Daytona, Escort, PDiKs) or very high rate of fire solenoid engines.
If you want some quick an easy upgrades for your DMR then switch to a wider bore grip/stock line and a wide bore line (maybe even EU QDs for better airflow). In some ways the line acts as the expansion chamber for HPA so having as much volume there as possible is a plus. I've got a 500mm 6.23 ORGA in my M249 and that thing chews through air like there's no tomorrow, but I've not noticed a massive fluctuation in pressure (maybe as much as 10psi at times). The real plus of this new reg is that it can operate at crazy-low tank pressures so that you can get the most out of your tank without needing to refill. That's the only reason I'm considering getting one, despite having a gun that's probably the least air efficient per BB that you can have.