Budget - I'm hoping to get a set of regs I can rely on for many years to come, so while I definitely appreciate affordability, I'm trying not to let a couple hundred difference be the primary factor in my choice of regulators. Looks like $850 - $1,300 is the rough range for a lot of doubles sets, and I can make anything in that area work if needed.
Service - I think it'd be cool to learn to service them myself, but not make or break for me. But seems like a nice bonus.
The ability to configure the same regs for sidemount would be cool also since cave training is in my future, and it'd be great not to have to buy a completely new set for that purpose.