Errr nope.
The PVR box will work just like the usual HD box.
Although it supports functions like recording, watch VOD content, all those are disabled once you're on Njoi subscription, making those functions to become useless.

yes and no.

i am using PVR with njoi account yes.

no becos njoi account will have the features of recording and VOD disabled.

There's been a rumours spreading around, suggesting that Astro are currently have no stock for Njoi set-top-boxes, meaning new customers that wish to sign up Njoi may not able to do so for a while (until they have stocks, which nobody knows when).
Another rumours also, suggesting that Astro may temporarily or permanently stop offering Njoi no monthly fee option in the near future. 
It feels like the end of Njoi is coming soon? Or it could be fake news? I don't know. Can't confirm about that.

If he doesn't want to pay for TV, then guide them on receiving/watching digital TV channels via UHF antenna instead. That one confirm no monthly fee. 
https://www.mytvbroadcasting.my/en/installation_guide/

heh