Re: but... but... but...
Iron Mountain isn't even that good, they lose shit constantly. Also, from a continuity perspective, they may be among the first but its more a gimmick than actual competency. The mine they initially used wouldn't have survived a nuclear attack, or even all that strong of a conventional attack with WWII era weapons, nor would the facility in Massachusetts that they like to hype up. Sure, OPM leases another hole near that one, but its telling that they don't keep their records for NSPD 51/HSPD 22 compliance there. Its just the retirement record archives that NARA doesn't maintain.
The old school Federal Regional Centers like in Thomasville, Bothell, and Denton have their uses as does all the "empty" floor space at Site R and High Point and the various other places like Ukiah, Kauai, the AT&T Project Offices, and (especially) the other parts of the continuity belt in West Virginia. In other words, just because you have a large company running marketing based on their supposed credentials and experience, there are far better ones out there, some of whom you probably wouldn't expect.
Just two and a half cents from someone working in this field.