Thumbs up for Grinnell - I built a 45' long curved walk with their products - came out great. I am going to do a patio at some point and will use them again.
ct67 - I have a big grade change out the back of my house. The limitations are 45 INCHES in height depending on the specifications, footer and engineering. They can be taller but would require some special things, each mfg can tell u about that for their systems.
What I am going to do is a deck for my top level and a paver patio for my lower level. This will keep me from having to bring in heavy earth moving equipment, fill, etc.
The Handyguys Podcast [url]http://www.handyguyspodcast.com[/url]