From a performance point of view there's not really anything between different CBs sufficient enough to make buying one give you a magically different experience than the others from a receiving signals point of view. Some have slightly better selectivity but on SSB and AM it doesn't really matter as even the worst is more than sufficient for 10kHz channel spacing and if you've a bleedover box it is because someone has been in there with a screwdriver or its down to the splattering signal of a nearby transceiver and if their signal from a couple of channels away is. Splatter -100dB or higher on the channel you're on from a station on a channel nearby then no amount of selectivity is going to remove that splattering signal unless you reduce sensitivity. There's not one radio that can magically dig signals out of the noise others can't hear.
Ultimately it comes down to what they look like and their ergonomics, how you operate them.