Had a CoPilot with our older son, followed by a LOCT as he got older. Got a WeeRide for our younger son.
Others will disagree, but for three reasons I favour the mid-mount LOCT and WeeRide. One the bike handles better. Two the child feels less like luggage and more like they’re part of he action – more chatter better bonding. Three, they can be fitted to full suss frames – if you n wan to be bounced around on a rigid bike, you can bet your children don’t (and if you do they still don’t). Four (I know said three) it’s easy to check they’re ok.
LOCT are superb, but a) really only for 2 yr olds plus and b) out of production and like hens teeth secondhand.
WeeRide are good enough, and you can use them for young children.
There are good rear and front mount seats, but mid-mount has it for me for even mild off-road.