I'd pair a Zelph's StarLyte stove with a suluk 46 windscreen if you want a fun, user friendly UL setup for your 600 mug (probably a size small windscreen). Esbit is nice, but alcohol is more fun to tinker with, and it sounds like that's what you're looking to do right now. Plus Esbit, er um hex amine, will probably gunk up your nice new SP 600 a bit. Horses and courses and all that. When it comes down to it, they are all light, uber light. But Alcohol is fun. It's silent, you light it, go do chores around camp and return 6 or 8 minutes later to your boiing water.
Also, not the lightest you can get but over time they add weight savings in efficiency - also works with both Alcohol and with Esbit - try a Trail Designs caldera cone sized for your SP 600 with either the Trail Designs 12-10 stove or the aforementioned Zelph's.