Yep, i always make all of my wands/grind them.
I'll probably lower the price once I hit level 106/is finally able to use my satan golds. As of now, I'm seeing if i can get the most out of it, though 500 seems a bit much.
I sometimes still use it, and that's why I'm keeping the price a bit high. It's still useful for me, but i don't really NEED it anymore.
As for the magatama in the video, it was ran back then when Kingly Raiments still gave the ornament "Defense rate lowered" instead of "Guard effectiveness."
Source of the change is right here:
http://onigiri.cyberstep.com/info/topic/update/2084 (The wording should be switched on the patch notes)
Back then, it actually lowered the mobs defense. If you noticed, Mobs took less damage the higher the level they were and this was due to the mob having very high defenses. Defense rate lowered essentially ignored a % of that and amplified your damage by a lot. That's why I was able to do effectively 30k more per skill when I had that ornament. However, now that it's changed, it's practically useless... :/
In comparison with the exorcism staff, i usually estimate that ougis are worth about 60~80 OC itself per, not to mention the seldomly seen evolved Crimson Ray. I do remember seeing that wand, and iirc, it didn't have Crimson Ray VI either. It's also significantly weaker than the Dogura Magura (I think). In any case, give me an offer and I'll get back to you. (I usually overshoot the prices for the sake of receiving offers anyways)