I just used SPAN for some "pre measurements" in my studio.
Since those measurements are usually about the lower frequencys (room modes etc..)
I would use pink noise (or even brown noise) and a high block size setting in SPAN.
Block size 8192
Average time 3000
make sure you put "offset" to center.
This gave me a good "realtime picture" when moving Mic/Speakers/absorbers in the room.
The actual measuring I did with REW. But SPAN certainly helped me!
@Aleksey I was missing a 1/24 smoothing on SPAN (and Gliss EQ)
I find the 1/12 just a lil to "coarse" and I notice that I use 1/24 all the time on REW.
Would be nice if you could add a 1/24 smoothing :)
for room measurements the 1/24 smoothing seems to be a standard
sent you 2 pictures :)