Bit of a naive question here. Are alien bees competitive with bowens type flash heads or more like lencarta level stuff?
Not a naive question at all mate

All three brands, Lencarta, Bowens and PCB will have advantages and disadvantages over each other.
I'm not too familiar with either brand but by looking at specs and noting the feedback, PCB gear has serious potential in the mobile lighting on a budget department, before the release of the Einstein (Buff's newest monobloc head), the issues with PCB gear were mostly related to colour temperature consistency over a sequence of frames.
The Einstein addresses this issue and boasts consistent colour temperature across all power level outputs and duration of use.
The cheaper AB heads will still have these issues afaik.
Lencarta do not appear to have any reputation in the negative side, it's quality gear at affordable prices.
There were accusations that Lencarta was rebadged Jinbei gear but this has been proven to be quite incorrect.
Lencarta use cases and outer shells from Jinbei but the inner components come from Germany and Japan.
Read more here:
http://www.lightingrumours.com/lencarta-rebadged-jinbei-products-306
Personally, I have a serious interest in Buff's Einstein and VII power sources, these items have a huge potential for my requirements.
Consistent feedback and review suggests that all three brands deliver good results.