I have Mk25/G250v regs for my doubles, and bought another Mk25/G250v/G250v for my singles setup.
This was after buying a HOG and diving it for awhile. I currently use it on one of my deco tank setups.
Will you be happy with HOG regs?.....They are a serviceable reg and many are happy with them, including a couple of guys that I dive with.
Will you wish you bought Scubapro regs for your singles tank instead?......that's likely, if you already dive and love another brand.
The HOG regs are a good regulator, at a great price point, in my opinion. They are not as nice as my Scubapro regs, in regards to what I like better.
I also have a few Dive Rite regs, which the HOGs are very similar to.
Most regulator choices come down to brand preferences and the intangibles, myself included. You won't really get a straight answer, it's so subjective.
Cheers,
Mitch