Which lakes in Missouri and Texas walley65? I ask because instead of buying two LakeMaster mapping cards, you may be able to get the lakes you need, along with the LakeMaster card functionality, by making use of the new Humminbird ChartSelect downloadable maps. Basically you provide the SD card, you encrypt it on your Humminbird unit, you buy then download and install only the maps you want to the memory card. These are the same maps that are on the current versions of the regional LakeMaster mapping cards. So you could get the lakes from Missouri and Texas that you want without paying for additional lake maps that you won’t be using.
Unless you want/need the additional 3D mapping, aerial pictures and all that the Navionics Platinum mapping cards have, I would stay with the Navionics Premium mapping card.