Both are very generic names that cover many specific models of radio.
Both ranges include PMR446 variants, and if the ones you have are both for the PMR446 band, they should just work if you select the same channels, and work with any other make of PMR446 radio.
For any other frequencies either series covers, you need a specific licence and transmitting without a licence is a serious offence.
The maximum penalties for illegal transmissions are unlimited fines & two years in prison.
If you transmitted on eg. ambulance or fire service frequencies and caused delays that harmed someone, you could be prosecuted separately for that.
Many surplus PMR radios include 'selcall' units that prevent them receiving transmissions not intended for that specific radio user, so just because you cannot hear anything on a frequency it does not mean other people are not using it.
Many also use duplex frequencies so can only work properly via a specific base station, not directly person-to-person.
[Radio & Electronics designer & programmer for 30+ years]