The Garmin Zumo 660LM is a good satnav, I use one myself.
If it comes with all the mountings & wiring for car and bike and is working OK.
£200.00 is not a bad price, but you may be able to pick one up a little cheaper. (keep a eye on ebay etc)
The Harley Road Teck is exactly the same satnav (just got all the HD dealers listed in it). These sometimes go a bit cheaper because non Harley riders seem to have a hang up about buying Harley branded kit.
To plan routes easily, it would be advisable to download via Garmin Express, the mapping software called Garmin Basecamp onto your laptop etc. This is a free to download and quite simple to do.(even I can do it)
The 660 has been around for a quite a while now and has been superseded by the 590LM.There may even be later model than this ?
I have both and to be honest I prefer the 660.
As with most Garmin satnavs once you have registered them with Garmin. You can get free mapping updates from Garmin again via Garmin Express.
I hope this helps