No monthly charge unless you want live traffic updates, we don't have that so not sure how it works. The difference between models is the "s" stands for speaking; meaning the street names.

We updated the maps; had some issues, but customer service helped us out. So the free update fits.

Yes, definitely. When you enter a destination, it finds the "best" route (depending on your settings this means either fastest time, shortest miles, etc) and if that route uses toll roads or bridges it will ask you "AVOID TOLL ROADS? Yes/No".

It does the same thing if there's HOV (carpool) roads, and also for dirt roads.

You can change the settings for either of these to not prompt and instead always avoid, or never avoid, these roads.

Sometimes applying heat, ie, hair dryer will loosen enough to pull off. Then use solvent to remove residue. Will need to purchase new circular disk.

The traffic and fuel cost by location are not free with the 340s. They cost like $15 for the fuel and the traffic I believe you pay by month AND you have to buy the receiver which is an additional $100 or so. I've used receivers with traffic on them and they aren't that impressive. They just tell you about major accidents and stuff. Not worth it in my opinion, but it depends on where and how often you would use it.

Yes

yes

No it has avoid roadblocks that's all.

I wouldnt think so because it has a Li-ion battery. i would recommend you to use the battery until near empty a few times to make sure the battery works.

no memory card can be installed, it has enough memory for what i need. It just depends on what you want on the product