Zumo 660 - Montana 600

[Legadema]

Would like to swop my Zumo 660 for Montana 600/650. I use to have a 276C and was probably the best GPS at the time, but it was stolen and bought the Zumo.  I use my GPS on bike and 4x4.
What is the difference between the two units?
Will it be a good swop or should I keep the Zumo 660?

 

[Snafu]

 

[Jacko]

 

[Legadema]

 

[Snafu]

 

[Crowley]

 

[Legadema]

 

[SGB]

 

[Jacko]

 

[ChinaPete]

 

[Roela]

 

[Ian in Great Brak River]

 

[SGB]

 

[Losper]

 

[Rickus]

 

[Roela]

 

[Moondog]

 

[Roela]

 

[jpcussen]

 

[Crowley]