Out of the box, the Shures came fitted with a medium sized plastic end. I tried this and while I initially thought it felt like a good fit, the sound wasn’t right (I couldn’t hear any bass at all!). I switched to the medium black rubber option, which looks nearly identical to the Fontopia, and the sound was much better.

Now I’ve used the Shures nearly every day for a month. Here are some things the Shures do better:

• The sound quality really is superior. They have less bass than the Sonys, but that gives a much more balanced sound (and remember if you can’t hear ANY bass, they’re not fitting well!) . The mids and highs sound fantastic.
• LOADS of different ear fitting options (3 sizes of rubber, 3 of plastic and 3 of foam), should mean they’re suitable for a wider range of ear canal shapes than the Sonys.

But here are some things the Sonys do better:

• They’re much smaller and lighter than the Shures (see photo below). Not only the headphones themselves, but the cable and plug too.
• They’re easier to fit in your ear. This is partly due to the smaller size, but also due to the strange way you’re supposed to loop the cable over your ear with the Shures. I think this is to support the extra weight, but I just find it annoying.
• Once the Sonys are in your ear, they just stay there. Even after a month of everyday use, I still have to fiddle with the Shures to keep them in the right place. I haven’t tried wearing them to the gym, but I don’t think they’d stay in for long if i did.
• They’re cheaper. Especially now the Shures aren’t on offer at Amazon!

To sum up, the Shures do deliver much better sound quality, but it’s at the expense of convenience.

Edit (April 2008): The shure headphones developed a fault after only 3 months so I returned them to Amazon for a full refund. I’m now using Sennheiser CX300 headphones, which are IMHO every bit as good sounding as the Shures, with the size and convenience of the Sony Fontopias. They’re MUCH cheaper too!