The Quilt Studio web ring is encouraging members to post on their experiences with fusibles. Since I used fusible web on the Fall Madonna, I'm going to throw in my two cents.
I generally stick to the basics in terms of products: I use Heat and Bond, both the sewable and the no-sew versions. The no-sew version has a stronger glue, and it is stiffer. However, it will not last forever through repeated washings nor through hard wear. The sewable version will hold as long as your stitching holds up because you don't have to rely on the product alone to keep your pieces together. It also has a softer hand.
If you try to sew through the non-sewable one, your needle will get gunked up with the glue and you'll have to keep cleaning it, which will drive you crazy. Recently I made denim patches with the non-sewable Heat and Bond by mistake, and patched some jeans, and since I needed to also sew through the patches, I cursed my way through the whole thing, though I did finish it.
In the Fall Madonna I fused individual motifs on the sunflower fabric with small pieces of Heat and Bond (no-sew). Because it will not be worn or handled, I'm not worried about the motifs coming off. I cut a piece of the product slightly larger than the motifs I wanted, and I ironed it down on the back of the floral fabric. Then I cut out exactly the motifs I wanted, positioned them on my background, and ironed them down. I used to be very precise in following the manufacturer's directions about how long to fuse and at what iron setting, but lately I just wing it, and everything seems to turn out.
On the Fall Madonna, I also ended up doing silk ribbon embroidery through the fused motifs, and my fingers were screaming in protest by the end. It would've been better to have used the sewable version, but I used what I had on hand, and wasn't thinking ahead very clearly.
When I'm working with any thing sticky, I iron a piece of freezer paper to my ironing board to keep it clean. I've also found that a crumpled up piece of waxed paper rubbed on a hot iron's surface will clean it thoroughly.