Do they still make the Sturdy-Lite? I think that may be a defunct product, so I'd be concerned about getting support from the Grace Frame company if you have issues or parts that need replacing (especially if you buy from an outside vendor).
Also, looking at the frame, it certainly doesn't look very "sturdy"! There may be a reason they're no longer making it...
I own a Little Gracie II, and it works well enough for me. Both it and the Start Right Frame are Grace's lower end products. If you're trying to stay low on cost, though, I would highly recommend checking out craigslist -- I see people selling their frames on there all the time, and usually for a pretty good price.