took about 4 hours in total. not nearly as much active work and cleanup as a batch of beer. however, here you can get great quality maple syrup for about $7 per 500ml bottle. the rectangular kettle is made for high evaporation. one tree gave 4.5 gallons over the course of maybe 10 days, and a lot was leaked onto the ground from the spigot. the sap itself has a just just barely detectable sweetness, people say something like 1 to 3% sugar. you could mash beer in it i guess? i dont know the pH.
taste is pretty good, i was worried about it being odd or sour. no sourness, much more woody than the store stuff, no smokiness, which you can taste if you get country maple syrup that was cooked with a wood fire. lighter colour than the store stuff.
would i do it again? likely not, barring some desire to make a very specific maple syrup or if i somehow was able to. but even then i can probably buy whatever variety i want for less than the cost of the propane.