If weight is a serious concern, then yes I would probably stay away from that particular bike, as it is most likely VERY heavy compared to higher end bikes. I assumed you were looking for something fun to bum around on with cost being the major factor.

This is just an example of a step up from X-mart store bikes, yet still somewhat affordable, and most likely much lighter. You can add a rack, lights, and fenders to your choice when you get it. Just go to the Local Bike Shop, and get some ideas on what you want (weight, comfort, function, etc), and how much you want to spend, and go from there.

http://www2.trekbikes.com/Bikes/City...7000/index.php

Just remember though, if you don't want to spend hundreds of dollars/pounds, then the Argos you listed is probably a decent bike to start off with. As for putting it together, how old are you? I am sure your boyfriend/husband, or father would be more than happy to help you with that. You may even have a girlfriend who is handy with wrenches. On the farm, my sisters could fix almost anything. But, as a father, I would not expect my daughters, or even my wife to have to assemble there bikes.

Good luck.