So, I am no expert, but I think I have somewhat of an understanding about lighting. I used to have the AB400 kit with a small soft box as my main light. I am not a reviewer nor have I done anything like this before, but I've learned quite a lot here, and thought I should share my experience, and thoughts to those who are in the market for lights.
So I sold the ABs- and was juggling and deciding between MANY different choices of monolight kits, including profoto 600/300 combo, Dlite 4, Dlite 2, Style 600RX, and some others. I bought the 400BX because:
1. They looked better built than the Dlites at first try at Vistek (looked like they can handle a big octabox)
2. Dlite 4s in Canada didnt have fans.
3. Elinchrom had reputable set of accessories and lineups for later additions.
4. PRICE. It had a lower than advertised rate at B&H at 1198 for the 2 light Kit, it seemed like a fair price. Not Alien Bee cheap. But a good price nevertheless.
I got the Kit, lightmeter and an Impact reflector with lightstand/boom all for under 2000. Which was my budget after selling off the 40D and 17-55 EFS (yeah yeah, I know.. I needed better lighting more)
On to first looks:
Setting up the lights was easy. Modeling light comes separate, the lights have no other assembly required other than putting on the modelling lights. They also provide some extra fuses (2 of each) -- I thought I needed to install it, but when I checked the fuse holder there was one in there already. I thought this was nice.
The speed ring is easy to use but it seemed a little stiff working with it, especially with the provided reflectors. I am sure I will get used to it. Compared to other locking ring mechanism, this one would be middle of the road. (better than Dlites)
The modelling lamp that came with the set is 150W Halogen, but you do have the option of getting the 200W one if you want. 150W bulb seems powerful enought even with the octa attached.
Performance:
Very Solid performance. Flashes were consistent after 30 mins of straight shooting for fun, the lights remained cool. (the fans start working right away, so for those who dont light much noise, this might be a factor - to me its a good thing)
The buttons on the back are big and easy to use... power goes from 2.0 to 7.0 at 0.1 intervals. So you have enough choices. Modelling light also has power options (I am not sure excactly how much as I just turned it halfway until my friend the model said, woah thats bright)
white balance is VERY consistent. I took a bunch of shots and checked with lightroom eyedropper on a white surface (my blinds) and the dial did not change at all.
Overall, I am very pleased with my lights. But better yet.. i am more happy with the 53" Rotalux Octabox! Yes its expensive at $300, the light is awesome. I didn't have a pretty girl to model for me today, so my best bud who came out for wings with me was my victim .. model. The light spread VERY evenly and in please gradation. At $300 I wouldnt have expected anything less.. My only gripe.. its a bit hard to get on and off the 400bx, but its so nice to be able to fold it away like an umbrella into its zipper bag!
I will post pics on my next post. Hope my blabber helps someone else.
. They may not be as robust, but I like their small size, and IMHO performance is equal to my 400BX. I just wish they made a D-Lite 100, the price of the 100BX seems a little excessive to me.
I'm with you on the D-Lites, they're the best value in budget studio strobes at the moment, IMO, and they give up NOTHING to the 400BX as far as the light they provide. I'm at the moment deciding whether to go with a 300RX kit next (I have the D-Lite 4 heads at the moment), or just save my money and get a D-Lite 2 kit for less than the price of one 300RX head, and be done with it! 

