Like DVD movies Canon printers and ink cartridges are regionalized.
Here is a list of the regions, found on a Chinese website, these are type numbers for ink cartridges. The first digit shows the region number. The list may not be complete nor error free:
Canon 125BK, 126BK/C/M/Y/GY for South America and Mexico market
Canon 225BK, 226BK/C/M/Y/GY for North America market
Canon 325BK, 326BK/C/M/Y/GY for Japan market
Canon 425BK, 426BK/C/M/Y/GY for Middle East and Russia market
Canon 525BK, 526BK/C/M/Y/GY for Europe market
Canon 725BK, 726BK/C/M/Y/GY for Asia market
Canon 825BK, 826BK/C/M/Y/GY for China market
The type number of many Canon printers show which region it is intended for. For instance printers intended for the European market often have 50 as the last two digits in the type number, printers intended for the US and Canada market often have 20 as the last two digits in the type number.
Of the two mentioned printers I would recommend the MG5320 as this printer uses the PGI-225/CLI-226 cartridges for which resetters are available. The MG5420 uses the PGI-250/CLI-251 cartridges for which no resetters are available. The PGI-225/CLI-226 printers are being phased out, so better hurry if you want one.
Canon printers will only work with cartridges for the proper region, so a bargain printer from Ebay or Amazon is no bargain if it is for a wrong region.