I've been climbing on a pair of PMI 8.1's for the last two years. 40.9 g/m, but what I like teh most about these ropes is that you can use them as twins or half ropes. PMI, in the past, has always been against making a twin rope becuase of the high impact forces. Take the Blue Water Ice Floss for example. The impact force is 10KN. That's higher than the UIAA's minimum open gate strength for carabiners! PMI has had their 8.1mm in their line for a while but they only sold it as a half rope. Then they decided to test it as a twin and see the results. The inpact force was only 8.4KN. That's less than their 10.5mm. What this means is that you can clip the rope any way you want, both in the same piece or one rope per piece if using them like half ropes. If the route wanders, alternate your clips. If you get scared, clip them both. No reason to carry a single any more, unless you want somthing burly or you're going to TR.
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