I would absolutely recommend DX boxes unless you are in a large facility with distributed audio needs where Dante is already an integral part of the architecture. If you are just trying to connect a stage box to a console use the DX boxes. Not only are they cheaper, but the built in proprietary connection is faster and more reliable than a Dante network IMHO.
While it is true you can use the A&H Dante boxes in the future with another brand’s Dante equipment, the fact that you’ll have to use the A&H preamp software to control the preamps (gain, phantom power, polarity, etc) would be pretty annoying. Annoying enough that it might be worth swapping gear out anyway. (Please note, this isn’t an A&H issue, the Dante protocol does not include standards for things like premap controls, so every manufacturer has to put the preamp control “on top” of the Dante system. You can’t control Yamaha Dante preamps on non-Yamaha consoles either).
The preamps are the same between the two boxes, so the only difference is the transport protocol.
PS – I believe A&H actually has custom processing chips that they have designed from the ground up in their Dante cards. They do not purchase/use the Audinate Dante chips and only license the use of the Dante technology from Audinate. One benefit to this is reflected in the fact that the A&H cards offer the same I/O count regardless of the sample rate (ie all 128 channels are available at 48k AND 96k). With the standard Audinate chips, the I/O count always seems to decrease when the sample rate increases (128 channels at 48k, but only 64 channels at 96k).
