I have a couple coming from TechSupplies to tinker with. Quite keen to see how they go, but I am not actually expecting that fantastic in terms of range, as here in New Zealand, the default frequency of 868.3MHz is, I think, illegal here. I will have to have a look on the Radio Spectrum Management website...
What this means, is that I will have to set them for 433MHz, but as already mentioned by others, this WILL effect range, as I would expect, as you are essentially de-tuning the antenna if not used on 868.
If I find the relevant information for NZ, I will post it here.
...or we could just wait for manuka to spot this and let us know!
EDIT: Attached is the NZ RSM info, for any other Kiwi's here. 868.3 is NOT legal here, so if there are any other NZ'ers here with these modules, you need to move the frequency to 433 to be compliant with NZ regulations...
869.025 - 870.015 is unallocated here in NZ - I don't suppose you can shift the frequency to here with commands? This is only 1MHz or so from the default frequency, and would still be a pretty good match for the aerial on the modules.
864 - 870 is also GURL here in NZ, and also not far away from 868.3...