If the $700 price is an issue, though the first bike you linked to ranges from $650-699, then the Raleigh from Websters ought to be in play. At $550 it's a nice price and I'd trust it more than anything from Amazon.

Also, BikesDirect has less expensive bikes than the Schwinn. Like someone has said you're not going to find an "upgrade" on Amazon. Keep your Denali and save your money.