The OP said they were going to use two Buzz boxes - so there shouldn't be a problem if they use StbEmu.
It should work on any service. Where I have had problems on some services is using the true MAC on one box and then trying to spoof that same MAC on a different box - I assume it is because they are grabbing more than the MAC address from the box when they connect. You can see on some panels (like IPTV Express) all the details of the connecting box - such as box model, MAC, Serial number and also firmware they are using - so it is possible that a service could block you if everything does not match.
If you use StbEmu and make up a fake MAC and use it on box #1 and then fake the Serial Number, firmware, etc. on it - and then use the exact same info on the second, third, fourth, .......etc box then I can't see how the service could differentiate between the boxes that are trying to connect.
NipPEr Is a diSh liCkeR!
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