Like said he's had what? 3 battle so far since the 4 year gap?
*The Zenom thugs
*Michael, a pure angel with no immediate "hatred in his heart"
*Miko's robot doppleganger
The Zenom thugs he used his Zero R's ability, Michael was immune however he used his own ability on his Satanic self, and Miko he easily destroyed when Kirin/Old lady(completely forgot her name atm) were struggling and forced into a defensive. Granted Kirin could have probably turned her into swiss cheese with his speed, he didn't for some reason.
If you mean Shin Zero R, Shin means "new" so saying New Shin is redundant and can confuse people with the SS ranked O-part Shin - who is currently Miko. Although the evil counter is manditory for the power to work I think Jio will figure some way around that. In the Inuyasha series he has a technique called (pardon my ignorance but I only know the NA version's name) Backlash wave in which he counters a powerful demonic attack by reflecting it and enhancing it's power 10-fold. However powerful this is it's only useable against demonic attacks and a "pure" attack can't be countered with it, making his strongest attack useless. Does that make him weak? No, because he finds ways to use the technique in a different way and/or uses his other abilities to trigger it.
New Shin is Useless when his fighting Angels, and those without hatred in hearts.[unlike Cross, his Rings shines as always
Back from ban-hood, I blame explosm webcomics