Problems:

a) quota feature broken
b) low hash rate
c) unreliability
d) 5-7 second flushes of old work
e) doesn't work well on coin switching pools
f) doesn't work well on faster block time/low network hashrate coins
g) lots of bfgminer errors
h) reports of I2C and SPI bus issues
i) reports of dead dies
j) reports of DC/DC problems
k) reports of good cubes degrading over time
l) apparent slow progress of firmware development/fixes
m) reports of higher than advertised power consumption
n) reluctance of KNC to accept problems
o) slow production/delivery rate
p) concerns for safety due to alleged fire hazard
q) report of ee design problem -> no resistive termination of control cable bus
r) report of ee design problem -> one PCI-e connector
s) report of ee design problem -> rPI
t) difficulty of access to web admin interface due to performance issues of rPI
u) reports of yield problem with Asics
v) list  of problems is getting bigger every day