Welcome to CowRC!
The RC Maintenance King!
Epoxy
Not the epoxy from the hardware store aisle.
Generic epoxy is built with generic jobs in mind, not the plastics, resins, and delicate parts that make up this hobby. That's why CowRC carries Bob Smith Industries' epoxy lineup, formulated specifically for RC use, so it bonds the way this hobby actually needs it to, without the guesswork of whether a hardware-store formula will play nice with your parts.
Beyond that, cure speed is the real variable across the lineup. Sometimes a repair needs to hold in five minutes so you can get back to the track. Sometimes it needs thirty minutes of working time to get a joint perfectly aligned before it sets. Having that range means picking based on the job in front of you, not settling for whatever happens to be on the shelf.
One tip from the team: think about the repair itself before grabbing a bottle. A fast trackside fix and a careful, precise rebuild call for two different cure speeds, and having real options on hand means you're never stuck waiting longer than the job needs, or rushing a bond that deserved more time.