heres my review about the speed stability between e392, k5005(ori firmware) & e398(telenor)..
about the signal:
e392 can boost the signal around 25-30%(i've tested it and manage to get rssi -61(before -81 with e372 maxis)
e398 & k5005 can boost up signal around 20-25%(manage to boost from -81 to -67)
speed stability:
with dc hspa+ both e398 & k5005 is more stable than e392
with k5005 i manage to get this speed

with e398(telenor) i can get this speed

both modem perform well on stability as it can maintain within the range of 16-24mbps(non peak hours) and 10-14mbps (on peak hours) but definitely i can get the speed above 10mbps all the time with both k5005 n e398, the ping also maintain around 30-40+ms...please be noted that im not doing any tweaking on these two modem..just plug & play only..
as for e392 the stability of the speed is less compare to k5005 & e398..
with e392 i manage to get the speed around 8-13mbps..


both speedtest is done after looking on the best spot to put the modem..
about the heat issue..im not facing any serious heat issue on both three modem..its only normal hot but not hot like boiling water till u cant touch the modem..
therefor i can conclude that if using dc hspa network k5005 & e398 is the best choice.but for LTE network it still cant be tested since im not subscribing to Maxis new 4g plan...but still both 3 modem is a future proof for LTE modem..thats all