Everybody thinks you have to bring the compound that you're making too the exact melting point or higher in order for it to go into a solution. When the reality of it is as you know it's not about the melting points it's about what temperature does the compound dissolve into a solution while in solvents...Sust is a simple brew to make. I would take it to 140F-150F. That should be enough to get it all into a solution. There's no need for super high temps. Anything I make usually goes into a solution by about 150F.
Heating it that much might help it from crashing, but it wouldn't matter if you took 400°F it will not help with sterilizing the compound....I heat all my test to 195 to 205 . To ensure no crash and that it's sterile