I have the Carl (have had it for years now) and it's terrific. I think I paid btwn $80-$100 for it. It will probably last me for my lifetime. I specifically got this cutter (rather than a Genesis) because the Carl cutter can cut thick materials and I use a lot of matboard and thicker chipboard. The Carl does a great job for me and the blades last a very long time.
For thinner materials, I use the Fiskar's trimmer that takes the 'I' blade. It has a wire so you can see exactly where you're cutting (works great!) and the 'I' blade now comes in Titanium which, according to Jennifer McGuire, should last a very long time (I have one of the Titanium blades but I haven't used it yet). This trimmer comes in various (maybe 3) sizes so there is something for everyone and it's very inexpensive (I think mine was maybe $12 to $13 without a coupon).
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