My favourite HQ choice at the moment is a weirdboy or better a Warp'ead. I like the unpredictable nature of this character and although I have taken unlucky wound from time to time or killed some of my own boyz when using it's psychic powers I still think the Warp'ead rocks. The ability to deepstrike the whole unit he is in (usually 30 shoota boyz) behind enemy lines is just lovely. Because of wound allocation rules I like to deepstrike behind my enemy's units and usually the juicy targets are at the back which is then the front (insert evil laugh). But also his two shooting attacks are nothing to be sniffed at. Because I pay the 35 extra points I get to re-roll the effects on the psychic table and you usually end up with something useful. The top result I try to aim for is a Waaagh! when my Dakkajet is on the table and I get to double the amount of twin linked Supa Shoota shots. 18 strength 6 shots that re-roll to hit is a real pain in the a*# for any unit because it can glance, pen or rip though infantry models.
The model itself was fun to paint. Nothing special though but I liked the open brain and glowing eye. I guess my opponents will see his glowing eye of terror a lot in 6th edition. I like the unit so much that I'm actually scratchbuilding a second weirdboy so I can field 2 weirdboys for those extra cheese kind of games.