It's kind of like comparing apples to oranges, both fruit but different.
Dirty Girls are small, light spandex type gaiters that are nice for keeping sand or loose pebbles out in dry, warm conditions. If that's what you need them for, then those should work, but I also think they tend to need to be replaced often since the fabric is kind of thin and may not work well in harsher conditions. They're really just like a spandex tube that you put your feet through and cover your ankles with. They don't have foot straps or anything like that.
For think mud, wet, cold, snow or harsher conditions, the Kathmandu ones I offered you would work better as they are longer and more durable. Not trying to push them on you, but IMHO they have a wider use range.
Depends on your projected use....