Hi! I have just started vaping last saturday when I chanced upon a brandless PV set while on holiday. I managed to sneak it back to singapore yesterday but am running out of cartridges... any idea if i have to buy a new set or all cartridges sizes are the same? My set comes in a small black box and just says 'e health cigarettes'. Bought in thailand MBK for 500baht. Is it more advisable to use those with brands? Thanks!