Nice to read everyone's responses so far.
Tbooe, the Rat Shack meter, IMO, is fine for this task. I have an analog one, as well as a calibrated digital unit from Monarch Instruments (Model 321 @ $259). Both read quite similarly head to head.
Obviously, I'm a proponent of this sort of objective assessment of one's system. Loudspeaker/listener position changes to mitigate room modes on the bass end, as well as effects of room treatments and subwoofer integration all benefit, in my experience. It is revelatory simply to measure, albeit somewhat imprecisely, the in-room performance of one's painstakingly-assembled components. My, what our ears/brains must accept simply in the frequncy domain as "faithful" reproduction!
Panacea - hell no, but anyone integrating a subwoofer/pair will likely be very surprised at the imprecision of plate amp crossover/phase/parametric EQ adjustments, for one. I recently spent a number of hours dialing in stereo "sub"woofers (10 inch Focal woofers with Adire ADA300 Class D plate amps - DIY))to even out terribly uneven 30-160 Hz in-room response with fairly inflexible loudspeaker/listener positioning constraints. The Adire plate amps are among the elite of their ilk, with dual crossovers, continuous phase adjust and 2 band parametric EQs (16-80Hz freq range and continuous Q adjust). Nonetheless, the physics of my listening room proved more complex and unforgiving even for this array of "tools". I did achieve +/- 6.5 Hz from 30-12,000Hz compared with +/- 12Hz before adding/dialing in the powered woofers. Subjectively, vastly more enjoyable.