For me it depends on the code, and the model
- I mean, it's not cut and dry, and modelling has quite a few steps to it, all of which demand their own skill. Coding I think is more relaxed, because basically the chances are, that if you get confused or frustrated, it's your own fault - you can step back and figure things out on your own terms. On the other hand, when things are complex with a model you are making, they are complex and all you can do it resort to a simpler model. This is especially true of UV mapping and rigging high polygon models.
Both are equally fun, it just depends on what you call fun. If you can model and texture etc, plus code - then you've really no excuse to be bored, there should be dozens of things you could be getting on with. I need to do both, for me, I'd find modelling really boring without something to do with the models (code), and if I was coding, then that would be boring with no media to play with. That's why I even learned modelling - because my lack of skills in that area doomed any project I had in mind.
So if you are bored modelling then do some code, if your bored coding then make some media. Personally, I think that people who can do both are very lucky and should capitalize on their skills. I mean it's usually the case that a coder can't model and a modeller can't code.
I think I'm quite a reasonable mechanical modeller, but a horrible organic modeller. Making buildings, hardware, guns etc, it's fun for me because I can envisage 3D shapes quite well when they are technical, even UV mapping and texturing the mechanical stuff is fun. But the thought of modelling a head sickens me :X - has anyone had a good look at the Bruce character models? - they look like Heroin addicts who've chewed their own ears off. Mechanical modelling has it's feet on the ground, you have an existing object or set of rules for the model, and it is fun to sit with a set of digital calipers and a scale model and recreate something. I imagine it's probably quite fun to make characters and head models as well, as long as you know what your doing.
