Alroy - Are you looking for a groupset or a bike? The first part of the post seems to indicate a groupset; the last paragraph looks like you're looking for a complete bike. The prices seem to indicate a bike...or the difference in cost between SA and the USA.

Tiagra works well. It's slightly heavier, and has nine speeds instead of ten, but it works in the same way as the more expensive groupsets. I used it for 7,000+ km, and upgraded only because I got a ridiculously good deal on an Ultegra groupset. I've kept it, and intend to use it to build up another bike sometime in the future. Also, nine speed parts (chains, cassettes, chainrings, etc.) are about half the price of the equivalent ten speed parts.

BTW, congrats on completing a marathon! That's quite an achievement.