Are we talking a smaller frame? LHT's definitely come with 700c (with the option of 26'' as well), but in the medium to larger sizes. Generally people go with 26'' when going outside the US/Can/Eu. 26'' is standard MTB size, so it's 'easier' to find tubes/tires in strange foreign countries. 26'' will take more crank rotations on the same gearing as 700c to keep the same speed, but that's about it. There's really nothing wrong with 26'', and often beneficial depending on what the person needs.

Edit: if you truly are wanting to get into touring, then yea, maybe looking at a bike like the LHT is a fine idea. If you're wanting to dabble in touring, but mostly just eleviating car-commuting from Columbia to STL, you have TONS of options. For one, you could simply ride your Steamroller / ss / fixed. 120 miles is nothing, really. At 120 miles, you won't need 4 panniers, a rack bag and a bar bag. You can get by with very little. As well, you could start browsing craigslist/ebay for something cost efficient to see if you do indeed want to do touring. $200-500 can get you something quite incredible on the touring front, and allow you "fully loaded" trips. A used bike is usually worth what you pay for it, unless you trash/wreck it. If you decided you wanted a newer touring bike, you could always sell your newly acquired, used touring bike and do so.

Keep the Steamroller and ride it to and from Columbia/St. Louis, especially if you *like* that machine.