I've actually become less enamored of mine the more I use it. I have a die that's supposed to cut two 3-1/2" blocks and I noticed two things - one it doesn't cut all the way and I have to yank the fabric off the die and snip the threads between the two blocks. Two - the blocks aren't accurate!! I thought the fabric was shifting as I rolled it through and tried reorienting the die a few different ways. Finally cut a single sheet of paper and discovered the die is bad; the blocks come out about 1/8th inch smaller in one direction. It's a die I bought new, but from an Etsy seller, so I doubt Accuquilt will do anything about it (and who is to say the next die won't be just the same; the packaging and serial numbers on the same die at Joann's all match). So now I have a whole stack of blocks that are 3-1/2 x 3-1/4. Great.
And yes, there is a lot of fabric waste, especially if you're cutting simple shapes like blocks. 1/2" or even 1/4" waste on each side adds up if you're cutting a lot of blocks. I can visibly see the difference; a big pile of waste with the cutter, and a few little strips of waste if I use a ruler. I have the June Tailor slot rulers and with those I get extremely precise cuts, more precise than I'm getting with that darn 3-1/2"-ish die, that's for SURE!
So I've decided that since my hands are still in good shape and cutting isn't a physical problem for me I'm not going to use it for basic shapes like strips, squares and rectangles anymore. I think I even cut those basic block shapes quicker by hand since I can cut WOF strips and subcut from there pretty quickly.
I'll keep using it for rag dies and curved shapes like circles and drunkard's path blocks, though. For those shapes and especially the rag blocks, I DO think it's worth it.