I agree with Skeeter, unless someone wakes up Navionics I would not expect them update the NVB programs anytime soon. Purchasing the Platinum edition (I think) depends on your curiosity and if you have the extra cash. If you do not purchase the Platinum chip will you always be wondering on what you are missing????? Personally I think we the customers need to put pressure on Navionics to treat us as a valuable asset. Right now they (in my opinion) are arrogant, because they have the exclusive on HB's SI units.
Please do not get me wrong I love my 1197c NVB unit and would buy it again. I am not satisfied with the way Navionics treats their customers.
No matter what you chose to purchase you can't go wrong, you will have a great experience when you run around and really see under the water.
First go out and get a 4 GB Sandisk Extreme III SDHC card to record your time on the lake. When you get it, you should start out at 2 to 4 mph, record the your day and just cruise the lake for a few hours. Then during the week review the tape their will be a lot that you missed. The more I review my recording the more I see. I use YellowFin to review my recordings, review at high speed then go back to specific areas and watch it at slow speed.
I hope this helps, enjoy your new toy.