ICE / CD Emulator Question

[Citroënbender]

I've been giving myself "Analysis Paralysis" looking at specs of the various CD stacker emulator kits (FWIW, brands crossed were Loudlink, Yatour, Grom, Xcarlink, Connects2) and have been surprised to discover how few folders of songs they can deal with in USB or SD mode.

What I haven't been able to determine is whether similar constraints exist with Bluetooth streaming. If you have a device with more than ten folders of songs on it (say, an iDevice or Android phone), are there limits to how much of this you can stream through an emulator using Bluetooth connectivity?

I don't want to change the head unit, just to augment the things it already does well and not have to deal with CDs skipping.

Thanks for any seasoned input!