MRT ptx and MRT ptx pro

[swords]

I currently have an original AMB rc dp transponder (large red one) but now have a 2wd and 4wd car so would like to have one for each vehicle rather than keep removing them. Have asked MRT via email about 3 weeks back but havent had a response yet. If I send off my red one can this number be cloned onto an MRT ptx or MRT ptx pro? also I saw a pdf online form which seems to suggest that I could receive 2 MRT ptx transponders for the price of 1 (£54 I think) if they keep my old red one. Has anyone recently done this as wondering if this was a limited time offer?. Will the MRT be compatible with all the same clubs which I have been using my current AMB rc dp transponder at? and also one last query, is there any differences between the MRT ptx and MRT ptx pro other than one has red and black wires and the pro has all black wires?
Thanks to anyone who takes the time to respond.