Correct me if I am wrong (I may be!) but it's VERY expensive to harvest SPS now, based on the current DEC prices of Wood, Grain and Stone.
I have converted most of my plots to those three base resources, but kept one SPS plot for comparison... VERY EXPENSIVE harvest costs ATM....
SPS Harvest costs
Approx 180 DEC or around 14 cents to harvest 1.2 SPS, so that's $0.14 for $0.06 worth of SPS, very approximately!
Wood, Stone, or Iron...?
Stone gets it I think!
WOOD -0.005 Production rate per hour...
STONE - 0.002
Stone is produced at 2/5 the rate of Wood so if there was equivalent exchange with wood I'd expect to get 187*5/2 = 467.5 DEC, so at 624 DEC for 1000 Stone, stone is more profitable!
IRON - 0.0005
Iron is produced at 1/10 the rate of wood, so if there was equivalence I'd expect to get
187*10 = YOWSWER, exactly the same! So there is equivalence between Iron and Wood!
REF
Final thoughts..
EVENTUALLY all of this will balance out, but it's not worth harvesting either research or SPS ATM.
So I've paused all my SPS and RESEARCH production for now to focus on the big three.
I'll keep an eye on the exchange rates there is literally no point harvesting SPS if you can just sell Wood and stone and iron for more, but I think pretty shortly, within 1-2 weeks things will level out so that SPS is profitable certainly on occupied plots with that 100% bonus.
And I'll put research huts back on the magical lands but with reduced PP to take advantage of the 100% bonus there.
But for now it's all about the three bases!