I'm new to this nuclear thing, so, please, tell me if I got something wrong.
It's a deadly cheap, deadly simple and deadly effective, but deadly risky reactor.
With no extra chambers and only two heat dispensers it can be constructed very, very early.
It has 367% of base effectivity, or 82% of maximum theoretically possible.
It can charge one MFE unit (through transformer) before exploding. Then it cools down for about 17 minutes (according to planner). MFE unit is set to emit signal when full, and is connected by redwire back to reactor. So, reactor switches off automatically, and without .
Also, some other precautions are recommended, such as activated redstone going over wood block and then inverted into reactor (for auto-switching off when wood is on fire). Not sure if it will work fast enough, though. And, of cause, wall of reinforced stone between reactor and your other significant belonging is highly recommended.
MFE is not recommended to be directly connected to anything else, but instead should be used to charge things such as lappack once or twice per cool down period.