next to no heat, don't count at the LEDs for a heat source, you be glad in the summer time, I am, even in Denmark a HID light can be too hot in the summer time, much more easy to warm the room at winter time then to cool it at summer time IME
and best strain I had to put me to sleep (also one of the main effects I use it for) is the LSD from Barney`s a bit triply effect as well, but damn, so potent that it put you right to sleep if you just smoke a bit too much, witch is`t much, as strong as VERY strong hash
here is a few pictures from one of the grows I had with LSD
and a link to the strain
http://en.seedfinder.eu/strain-info/LSD/Barneys_Farm/
I also had good experience with Skunk 1# (LSD is a cross between skunk1# and Maza)
and good luck with the Hans Panels, they are the best of the best in form of quality inside and prices is`t bad at all, and pretty local compared to Area-51 witch would cost a bit in Vat/Tax as well to have shipped to EU
the Hans panels is a bit small in size compared to many other panels, also why two 80W would be needed to cover your room but IME its way better to have multiply smaller panes then one big, as you cover the ground much better then with all the Watt concentrated in one panel
hint: no matter what kind of LEDs you get or for that matter any artificial light, but special LEDs and special them Hans panels as they run with out lenses, will do best with some kind of training, a Scrog work very well with LEDs but attest some LST and/or topping/FIM