I've got the JRC Radars and cannot fault them at all.
A very useful set of features, I especially like the 3 way on/off toggle switch which makes things a doddle when setting bobbins etc. Switch to the right and they're on, in the middle they're off, and to the left they are on but with a neat little nightlight to show where they are in the dark.
Battery life is superb, (I'm still on the originals with no sign of them giving up the ghost), and separate tone/volume/sensitivity controls.
The receiver is a little "plasticky" but that doesn't bother me as it is either on my bivvy table or hanging from the brolly.
I would highly recommend these for the price.
Just under £95.00 on ebay for the all blue set (which I have because blue is cool!)...
https://www.ebay.co.uk/itm/NEW-JRC-Radar-CX-3-1-Carp-Fishing-Bite-Alarm-Set-Blue-With-Case-1411118/132764328259?epid=2255211171&hash=item1ee95ee143:g:1f8AAOSwA3dYHe4q