If you get a 998 I'd specify that I want a heading sensor gps puck.... I didn't know about the exchange program and mounted mine and now it's 200 bucks to just upgrade the puck so I can tell which way the boat is pointing. I'm still a little aggravated at them for sending the puck without the heading sensor, and not giving me the option for the upgrade for the price they charge for these things and so now they want 200 more dollars just so I can tell which way my boat is pointing on the chart. But like I said don't open the puck and they have an exchange program for 50 dollars extra which would be well worth it. Without speed these 998's have no way to tell which way the boat is pointing and pretty slow to upgrade at slow speeds or any speed really. 999's will be the same way and 1198's and 1199's too... I'm sure if you ordered any of the 98 series you could just pay 50 extra and get it sent with a heading sensor puck. And on the new 999's and 1199's they have internal gps so no exchange program for them, to get a heading sensor you will have to pay that extra 200 for a puck with built in compass (heading sensor). Just another way to squeeze another 200 dollars if you ask me doing away with the exchange program and built in gps on 99 models.