116 of 121 people found the following review helpful The 660 model is a better choice for me, April 22, 2017 By DGmo – Verified Purchase(What’s this?) This review is from: Garmin RV 770 NA LMT-S (Electronics) I give it 2 stars, but I’m sending it back in exchange for the RV 660LMT instead. The most significant difference is the traffic information. LiveTraffic is provided through the Smartphone Link, and is the most current and most often updated (FM receiver is least, then HD, then LiveTraffic). The 770 requires your phone and bluetooth connection to provide LiveTraffic, but the FM or HD is only available if you add the purchase of those specific power cords (add another $30 – $70)?. The 660 includes the power cord with FM, but Live Traffice is available by Smartphone Link at no extra cost. I want to make only one Bluetooth connection at a time (at least with current my phone), so I must often choose between connection to Garmin or with vehicle. Additionally, if someone is wondering if another Garmin’s power cord can be used interchangably, Garmin informed me that power will be supplied, but the FM receiver for traffic may not be; assure you have a compatible systems if that is a desire. I like the option on the 660 of leaving my bluetooth connection for the vehicle instead, while I can switch over when I want. Given all the comments about bluetooth connection issues, I’m not going to take the chance on the 770. With the price difference of $150, more if one adds a power cord required for traffic, I’ll opt for the smaller screen of the 660. My other minor complaint is that the larger screen on 770 doesn’t seem to provide any more street names or map area, rather the fonts and roads are just bigger. I prefer to see an extra mile and more street names instead. Also, the speed limits are not shown correctly; it is providing to me the truck speed limits instead of passenger vehicle, even though my 26′ 12,000 lb Class A with no trailer qualifies for a passenger vehicle speed limit (as verified with Michigan State Police). I consider myself responsible for knowing posted speeds, but given that I cannot turn that feature off, it is annoying. Regarding updated POI’s (RV parks, campgrounds, services, etc.), each will be up-to-date with every map update. I am a loyal Garmin customer, but the 770 doesn’t make much sense to me. Garmin, give away the traffic antenna, or sell them at a reasonable price.