nRF24L01 interoperability/different sources

Anyone have experience with using nRF24L01 modules from more than one source? Should they all work together? I see photos of at least two different designs for sale, some with a '7' shaped antenna and others with a zigzag antenna. So far, I haven't found clear specs of what '2.4gHz' amounts to on these things. Is the spectrum channelized is a well-defined manner (e.g. like CB radio) or up to the whim of the manufacturer? At least the boards seem to all share a 16.000mHz xtal so presumably they operate on the same frequency under control of the nRF24L01 chip itself.

I found and bought an ebay auction with 10 for $15 (zigzag style) after finding and buying 4 with the '7' style which were about double the price. I hope this won't be a 'you get what you pay for' experience.

Both claim to do Enhanced ShockBurst, by the way. Still waiting for delivery from China so I can't actually try them out yet.

I believe they are both reference designs from Nordic, the zigzag one being newer. Therefore, I would suspect the 7 modules are older, and may actually use the older nRF24L01 (not the newer nRF24L01+). The + will talk to the older modules in a common 1MHz mode, so they are backwards compatible, but there are more options when you get two + modules communicating.

I think you hit on the key difference. I see no mention of the 256kb mode on the '7' auction. I do for the 'zigzag' auction. So the 2nd batch I bought seem to be the nRF24L01+. Good news. Nordic says they are supposed to have greater range and be more tolerant of other nearby 2.4gHz devices.