A few years ago I switched to using esbits on my 3-season solo trips. The commonly cited downsides smell (you get used to it) & residue on pot (I found cleans off with my used tea bag) are pretty manageable. The plus side is that they are pretty weight efficient if you have a good stove/windscreen/pot system and it's really easy to figure out how much fuel to bring. I have a few more notes on my recommended stoves page.

--mark