Given that you'll need periodic servicing, you'll want a model that at least one area dive shop will service. This will still probably leave multiple options.
There are threads debating various options; Atomic Aquatics vs. Scuba Pro, etc... I dive an Atomic Aquatics B2; I tend to avoid highest or lowest end, and the swivel sounded nice. When the 2nd stage cover came off and was missing in Bonaire, it took some doing to find one shop that could sell me another; when I had a 1st stage failure in Roatan, the dive shop at CocoView Resort couldn't fix it (they rented me another 1st stage). I suspect a ScubaPro regulator would be more likely to be serviceable by foreign dive op.s.
Some people like the Deep6 reg.s, because they make it easier to service yourself. I have no intention of doing that, but it's an option.
I took a quick look at Scuba.com; it seems there are a range of different regulators that fall under ScubaPro M25.
Richard.
P.S.: a used regulator might come with an octopus; a new regulator might be sold without one, so be mindful you might need to add that cost when price comparing.