Another good price for an outstanding Dash cam, just in case you don't fancy the Dual model. Again I mention; a very good quality dash camera as reviewed by @neil.
Check out his review: https://www.ozbargain.com.au/node/420945
 
    Another good price for an outstanding Dash cam, just in case you don't fancy the Dual model. Again I mention; a very good quality dash camera as reviewed by @neil.
Check out his review: https://www.ozbargain.com.au/node/420945
Referee: $10 off 1st purchase.
Referrer: $10/$20/$30 off $100/$150/$250 Spend.

Good find.
Why not post it as a deal?

How is it a deal if it's
slightly more expensive

You don't have to buy 2.

Because you'll likely neg it

Is there a single camera option on sale?

Yes, this deal is for two single cameras. Not the dual camera.

Would you run this as a dual camera system?
Or is it best to get a dedicated dual camera system?

https://www.ozbargain.com.au/node/433612
People do. If you have a power socket in your boot or are confident to install your own, go for it. Otherwise, probably best to get the dual one.
There's pros and cons of both options.

How does it compare to Xiaomi 70mai?

The power adapter/cig plug causes interference with my radio

Try ferrite clamp on power cable at the camera end. 
https://www.jaycar.com.au/u25-ferrite-voltage-spike-protecto…  or similar to suit your cable diameter.

anyone want to go halves near Bayside Melbourne?

Looks like it expired?

looks like price went up to 145.

Is this dash-cam able to be hardwired to ACC?

Yes, The B1W is one of the least power hungry dashcams. Tested the custom firmware with default Wifi Off:
While recording: 5.12V / 0.25A = 1.28W
While in parking mode: 5.11V / 0.24A =1.23W
slightly more expensive here
https://www.aliexpress.com/item/Blueskysea-Car-WIFI-DVR-B1W-…