Garmin 450 for the last 3 yrs...flawless, yes it's waterproof...
But I bought it for the piece of m ind, plus built for motorcycles IE vibration,rain, etc...
When it fails I'll get the latest and greatest Zumo again

What I like about GPS is you can zoom in and anticipate the road if it's full of twisties..
Or the the good ol, "hey thats looks like a good road I'm taking the left"
Of course, gas food,lodging..etc

 

The Garmin 855 ($139 online at Wallyworld) Buy a Ram mount axp $60 and carry a baggy with you for the rain. if you have a radio you can plug in the this gps and hear the directions thru your speakers just fine!

 

I have the Street Pilot 2720 on my bike now. The SP models have been discontinued. So I bought a Nuvi 550 that is waterproof for around 200 bux. It just depends on how much you want to spend, 100 or 1000. Its your money.

 

Currently I have a Nuvi 1490T. I will eventually upgrade to a Zumo 660 or 665 when I have the funds.

 

I have had a Nuvi 760 for 3 years and it works great...bluetooth, MP3...i put a ziplock bag over it if it will rain...i believe it's discontinued now...get one with the bluetooth...Garmin is preferred....The one for the bikes are nice and waterproof but pricey...if money is no issue get the nicest one you can get.

 

I think for the most part they all work, I have an ipod that I plug into my radio so no need for one that plays mp3, but some love that feature, I hardly listen to the voice commands in my car, so don't realy care if I hear them on my bike, I have it mounted where I can glance at it so I know where the next turn is, pluse most of them list the next turn and how far so you can antisipate it.
I think most of the units built now are all solid state so I doubt that vibration is a real issue, but rather a selling point for the higher priced ones.
I have Garmin mobile XT installed in my PDA which I have used for years, (still do when I don't have my magellan with me) but they have stopped supporting that since they have their Garmin phone, so I just got a Magellan 1475T, it has free trafic for life, shows which lane you need to be in for the next turn, or exit, it seams to navigate to the next turn accuratly, but then it uses Navteq maps, which most of the US models use now, so they are all going to be pretty much the same.
Mine is not water proof so I carry a baggy as mentioned by some above, I just noticed that Magellan now sells a motorcycle mount for this model so I guess they are saying it IS sutible for motorcycle use, and I paid under $200.00 for it complete.
Terry

 

Great thought. I own the Garmin 765T and it does everything the official HD one does for hundreds of dollars less. I have a friend that has to have everything official HD. He was telling me how great his is because it says Harley on it when you boot it up and he can find all of the dealerships on it also. He didn't have much to say after I showed him that mine can boot up with a Harley Davidson screen saver that I found on the internet and can tell me where all the HD dealers are after uploading a POI from one of the members here.

 

I got the Garmin 665 because I wanted the xm. Dont think anyone hates it but it is alot of cash and it makes you double check the mount and pull it off so it doesnt get ripped. So if I had it to do over, I might get a cheaper unit that you dont care about if it bounces down the road.
The one thing I do like is the work Iron Cross did on the head unit. Had rear aux input and rca jacks added for amp. They are fast and do good work and it makes the gps install cleaner. Zumo is nice but disposable has some benifits.

 

I don't think you can go wrong with the Garmin Zumo's. I had the 550 and upgraded to the 660 when they came out, and now they have the 665 with the weather/radar on it too - which could be VERY helpful if you're out on a bike and the weather SHTF.

 

I have a Zumo 550 and I think its great. I had a couple of cheaper ones on before the Zumo, they were ok, not as many features as the zumo, wasn't waterproof and they were a pain to but on and take off with the wires. The zumo unsnaps easily and there aren't any wires to disconnect, there all in the mount. Also it has blue tooth, XM and weather. I think the GPS is the best invention since the map