Is the SMS-1 graph the same as the REW graph?
I had a Omnimic and at the time my REW laptop was still functioning. In my comparisons the SMS-1 was close enough that I use it to measure my DIY subs all the time. It's just more convenient as all I have to do is connect the mic and I am measuring in a minute. I can also adjust phase quickly and tweak my subs much quicker than REW or even omnimic and I don't have to drag the laptop around. The only drawback is you only see the response to about 200hz but I only build DIY subs, not speakers anyway.