For Room Correction DSP/Software- How often do you use it?

The room correction software can help smooth out FR in the final step of room tuning your system. You still have to do speaker placement, room treatments, component matching, etc. Yes, I think it a good investment. As for what is achieved you can see the FR before and after graphs in my system profile.

I have used both Audyssey Pro and ARC and have achieved good results with both as long as you use a calibrated mic.

I use it all the time.

OTOH, I recalibrate it only when something in the system or room is changed or replaced.

I've used room analysis tools (calibrated microphone and REW) and adjusted PEQ in Roon. This can be very useful in doing what I did set your own filters as well as analysis of room if you want to use traditional style room treatments and speaker,  listening position placement. Full use programs like DIRAC and ARC are easier but I've never been a huge fan of either. I've gotten better results using REW. 

With that said the one quick use full program that in my opinion and use case  outperforms Dirac or ARC  by far and REW is GLM but it is proprietary to Genelec smart monitors. As for getting an excellent FR with minimal room treatments and incorporating subwoofers I've used nothing to beat GLM it is that good.

So what changes in your room that you need to use it very often?

For those that own such devices how frequently do you actually use it and what drives the need for its use? 

Um, every day?? I mean, I have configured it once, but I listen to it whenever my stereo is on.  I wrote about it extensively here: