Cool - secure lockup.
How big are you? If you're concerned about the bike holding up, I'd skip the front suspension altogether. Cheap front suspensions are cheap, heavy and not overly sturdy. I'd suggest something long the lines of a cyclocross bike or a flat bar hybrid like this trek -
http://www.trekbikes.com/us/en/bikes...ss/fx/7_2_fx/#
Of course, you can find similar bikes in any model line including bikesdirect, just throwing that out as an example.
Another thing to think about is that the new model year is upon us! Exciting news for people who want a discount on last year's bikes.
Or find one that somebody bought because they were going to get in shape and never really used, like this one
http://phoenix.craigslist.org/evl/bik/3184824995.html
(No idea if that size would work for you, sounds small)