Are you planning to use your dsm or a long/mid arm machine. If a dsm you need to imagine the design depth will be narrow, and there will be a lot of bulk build up in the throat as you advance the quilt, so that design will be smaller. I wouldn't touch these small frames myself unless I only made cot or lap quilts, too much fudging for me.
And if you're only making cot or lap quilts, you probably don't need a frame anyway. I would like to see someone demonstrate by completely quilting a big quilt on it before I would consider it. And that demonstration would have to include how to prepare the quilt before it's placed on the frame.