As long as you go into it with the understanding that you are not going to make back whatever you spent on the device - not placing any value on any "fun" or learning you would derive from the purchase - go hog wild !
I don't know where you get the statement that you won't make anything back....IF mining were not profitable NO ONE would do it. Now granted you shouldn't go into it if you pay crazy rates for power, but if your power rate is reasonable then you most certainly can make money mining. Accounting for the diff going up at $25k per unit the SP50 would pay for itself it in less than 9 months. Everything after that is profit. Even if the diff shot WAY WAY up so what. Instead of taking 9 months to ROI it takes 12 months. The point is, as with any investment, you have to be patient.
they should price it at $25K and stay there, but they won't, unless something changed with their approach to pricing.
Historically, SPT priced initial batches way high, then precipitously cut back on pricing-not a very good policy from the initial customers perspective.
You were basically penalized for buying early, which is not good-you want your enthusiasts to stay engaged.
$25K price would generate a tremendous demand, in my opinion, while pricing it at 40K-45K-much less.
we also don't know their manufacturing capabilities, maybe they cannot even manufacture enough when priced at $25K.