Hi Mike, I know enough to be somewhat dangerous I suspect!!

Cloning provides a mirror copy of the original disc creating an EXACT copy of its contents, including the master boot record (MBR), slack space, and any unused space.
I used a FREE program called: EaseUS Todo Backup Free 10.5 to clone the PG drive. Wouldn't say it was quick (about 3 hours for transfer of BIAB) as I took the option to copy sector by sector and just have USB2.0, but the results were excellent as far as I can see. As in above posts the only problem was with me trying to give both drives the same label letter. The actual cloning worked a treat!
I used another free program AOMEI Partition Assistant to merge the unallocated space on both drives.
Thanks again for your valuable input.
Kev