I must be reading that page wrong. Do these bikes really only come in one frame size each?
That is a dead giveaway that a bike is to be avoided. The three most important things about a bike are:
1) Fit;
2) Fit;
3) Fit.
No bike is a bargain if it's painful or uncomfortable to ride. A bike that doesn't fit will end up gathering dust because you will find reasons to avoid riding it.
"One size fits all" is a dead giveaway of compromised design, of bikes intended to be sold in mass-market outlets by sales droids who know absolutely nothing about bikes. If one of these bikes fits you, it will be a matter of luck.
The most basic bike shop bike -- find a shop that sells Fuji or Jamis if you're looking for low price -- will come in three or four or more frame sizes. Once the correct frame size is determined, the shop will swap stems and handlebars and seatposts and saddles until the bike fits you like a comfortable shoe.
You don't need rear suspension for riding on pavement and easy trails. And low-end suspension components will just break; they add inordinate amounts of weight and complexity to a bike that, if it's inexpensive, should be designed as simply as possible.
Example: for about $350 you can buy a Jamis Durango Sport SX. 28 pounds, quality aluminum frame, all brand-name parts, five frame sizes available.
http://www.jamisbikes.com/bikes/spec...ortspec02.html
A bike like this -- or comparable bikes from a number of brands like Giant, Trek, Raleigh, Fuji, Specialized -- sold and fitted and serviced at a good bike shop, will last indefinitely and ideal for the kinds of riding you plan to do.
RichC