I have been carring a a Merlin/Harpy for about 10 years now and for it's size it is an excelent knife. If you cut anything involving fiberous materials like rope, carpet or even linolium it is hard to beat. I have used mine on everything from 11mm climbing rope to seatbelts and it has never failed me.
The Zytel handled Merlin runs $35-45(but it has been awhile since I bought one). The best prices I have found on Harpys are $71 for the G10 version @ ABC-direct.com and $55 for the SST @ discountfirearms.com
Best of luck!
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If you try, you may fail. If you don't try, you certainly will.