I use exactly what you mentioned most of the time. The 5 minute variety does seem to yellow over the years, but I don't really care. If you want to avoid the change in color, the other two part in the syringe that takes an hour to set up works, but it takes a while to get hard (obviously). I have also used an epoxy paste from the same company as the syringes I think, It comes in roll that is blue on the outside and grey in the middle, you cut off what you need and simply knead it by hand until it is a uniform color and mold it into place. It can be a bit neater and I have sanded it to a desired shape, it stays a creamy greyish color, not clear. However, back to your concerns, until cured they all stink to high heaven, and should be used with adequate ventilation. Maybe the fumes are the reason I typed all this and never really answered your question!
