The biggest problem messing with HWID change is the risk of some incompatibility of firmware and hardware generally. Retaining HWID when cross-flashing is preferable because it [usually] easily gives you a safe recourse back to original firmware.

Sometimes a boot.bin [Ldr.bin] from the original firmware won't work with the desired main software [fw_all.bin; fw1_resources.bin etc.] to flash the relevant regions so we can't use it without further manipulation of the main software, either that or we take the chance and just use the native boot.bin. An example of that is [Only registered and activated users can see links. ], they have different HWIDs but same [Only registered and activated users can see links. ] and despite their hardware being identical the 37x0 boot.bin is incapable of dealing with the 34x0 firmware, although it can do so if the firmware is [Only registered and activated users can see links. ] first thanks to kunix [that's what i mean by further manipulation and it's another story and not a given for other units either]. So we just use the full 34x0 fw for the conversion.

However, if the original boot.bin does work and the device successfully runs the intended fw then we can be totally confident that so will that fw's native boot.bin work with it's own fw. Therefore we can do a full flash during which the HWID is also changed and the device is effectively fully converted. There are numerous other examples of that: nuvi 2460 to dezl 560, nuvi 27x7 to dezl/RV/Camper 760; nuvi 5x0 to zumo 2x0, nuvi 2x5W to nuvi 465 etc. where hybrid flash works and therefore so will full flash. If hybrid doesn't work only because of an ineffective boot.bin then it doesn't mean that full flash won't work but it's inherently riskier.

Now we can assume Edge 1000 Explore to Edge 1000 is fully compatible simply because it's running properly as a hybrid although regardless it would be prudent to test out it's real world use for a reasonable period before being the first to make the full conversion.

I hope that puts things in perspective for you. The explanation is perhaps over-simplistic and will make our Navigation Software Experts' teeth grind but in layman's terms it makes reasonable sense.