I like using a double hoop. there are several sizes but I prefer the bigger one. You can also take it apart and use each hoop on its own or transport it dismantled, a nice feature when taking it along in a suitcase. I have this model and I also have a single Dritz quilting hoop. Actually I own many hoops but this double one is my favorite. I also like the composite material this is made from instead of the wooden ones.
MORGAN-Lap Stand Combo 10in and 14in Hoops. Lap Stand has a unique tongue and goove no-slip hoop configuration which holds the fabric taut while working on your project. These lap stands are designed to elevate the project hoop above the lap while the unique feature othe this stand is that it is collapsible. Each stand is composed of two hoops held together by three supporting rods which space the hoops 4.5 inches apart. Simply invert the lap stand to work with either size hoop. Made of plastic. Hoop sizes: 10in and 14in diameters.
http://www.overstock.com/Crafts-Sewi...1/product.html
I bought my double hoop on a quilt show. You can use a hoop, double or single, for very big quilts. The double hoop will lift it off your lap. It can be used both ways with the larger or smaller hoop to the top.
Like some one mentioned the floor stand hoops might not be as easy to use when doing a larger quilt. Actually if you want a floor stand one you might check your local Craigslist as I see them frequently in my area for sale.