Yeah, I was going to compare, but I only had coke and ginger ale. I could measure relative to a Wild Turkey fifth, maybe laying on edge; there must be a conversion program online somewhere.
More seriously - depends on what you want for carpet. At least so far my Crypt Wendtii is staying under about 4-5", which is not that much shorter than a mountain dew can I guess. That's hardly a carpet, but it's in a 30" tank, and all I want is "low", something for fish to swim under, and I don't have to trim (much). So far so good.
I tried a real carpet (dwarf hair grass) and it died, rapidly and completely.