Dual pane windows are well worth the money.
I ordered them on my BC3450TS and don't regret it.
It does add about 150# to the rig weight though and does take a lot of weight out of your wallet, so I guess it balances out.
Take the time to order your unit and get exactly what you want.
Take the time and go over the option list, and compare that with what the dealer tells you and what you find on the Heartland Factory site.
There are sometimes differences between the three (3).
Then you can start asking questions.
You may also want to think about a fireplace.
We love ours, wouldn't be without it.
We use the parks electricity for heat instead of our propane.
Good Luck and Have Fun.
Hockster