I'm not a welder either but bought one and looked at a few Utube videos and taught myself to weld...rough at first but now an OK "back yard" welder that comes in handy for the odd small job. If your keen, go do a TAFE course, their cheap and could be a skill you may use around the house in the future. A little secondhand Arc welder is cheap <$80 will do most little odd jobs.
The kwiktech option looks OK but more steel than necessary (ie: more cost) than if it was welded based on the web page sample size and likely due to using plastic connectors.
For a small shed of this size, wouldnt really matter what you used (timber or steel)