Pocketwizard Flex or Plus II's

I'm going to try a little off camera lighting very soon. I will be using my D3s and sb900. I'm going to purchase a basic Westcott 28" softbox and Manfrotto stand. I have intentions of upgrading to Einstein's in the future, but not too soon. May also add a Vivitar 285hv before upgrading to the strobes. I will mainly be doing portraits of 1-3 people, mostly family.
I can't decide if I want to stick with the basic Plus II's or the Flex. I like the Flex, but coming from Canon I know there were problems with interference. Would you folks recommend the Flex over the Plus II's? I have also considered other options, but have decided to use Pocketwizards. I also don't see any reason to use the Mini. The size is not an issue as far as I can see.
The cost difference is negligible, I want a product that will give me the most consistent results with the least headache.

Please don't hold it against me for switching to the darkside...

I appreciate any opinions/input provided!

I recently went through the same thought process as you, and I opted to start building a wireless system based around the Flex TT5. I also have Elinchrom strobes and the Skyport system. I find for my work flow that I am very happy with BOTH wireless systems. And I have to thank a poster on this Forum who pointed out that I can use the Flexx with a Skyport stacked in it's hotshoe all on top of my Nikon hotshoe for even greater functionality in terms of "Hyper Sync".

I'm very happy with BOTH choices that I've made.

It was pointed out to me that the Plus II will not allow me to adjust power settings when using the MC2 with the Einstein. This has me leaning towards the Flex.
I've also considered the Elinchrom 600rx system. I finally decided the Einstein will provide the simplest one strobe option. I've read threads regarding this over and over, which gave me have a headache!

I understand your choice. I consider it luck when I walked blindly into a great deal on Elinchrom Style RX 600 and Skyport system (incl USB Skyport) as I had been looking at Einstein.
I think you will be happy with your choice.

Used to use mini/flex/ac3. Now use simple Plus IIs. This is with both speedlites and AB strobes. I like the manul power control option of AC3. Other things I care less. But problem was triggering when using my L358.

Thanks for all the opinions! I ordered a couple of Flex's today, along with the stand and softbox. I'm not 100% set on the Einstein's. Their my choice right now, depending on how long before I'm ready to "upgrade" that could change. I've also considered the Elinchrom 600rx using their skyport system.
I figured I'm better off to start small and work my way up.