Hi Tim, Robert turned me onto this thread.
I'd definitely recommend sticking with the same brand for the monolights and the pack - having two sets of modifiers, two repair centres, two local dealers, e.t.c. will cost you a lot of time and money. You'll most likely end up spending as much on modifiers as you do on the strobes themselves. Not sure if it applies in this case but it's also worth noting that different manufacturers build their lights to different colour-temperature specs so you could end up having to deal with mixed lighting. What is it about the Dyna-Lite pack that you can't find in the Elinchrom range?
I have to disagree with Wilt about the inflexible power settings of packs not being an issue - moving strobes backwards and forwards to increase/decrease the light hitting your subject is not being in control, and in my mind is definitely not an acceptable compromise in a studio. You should have the capability to decide on the light spread, position and relative size of the modifier and then set the power level you want, rather than being forced to position your lights based on the output you need and accept whatever size & spread you happen to get.
Personally, I use Elinchrom RXs for studio work (each one can be adjusted through a six stop range) and I only break out a pack when I need more than 1200ws of power (very rare). The boom issue is solved with these lights as you can set the output by remote or by software. It's true that they are heavier than pack heads but they're still only a couple of kilos - any half-decent boom will be able to support them, and as far as I'm concerned any boom that can't support such a small amount of weight is a safety hazard regardless of how heavy your lights are.
Hope that's given you another perspective. Like I said, I don't use packs all that often as they don't give the degree of control I need for studio work, but I do have some experience with the Elinchrom range so if you need any info I'll do what I can.
I agree with everything Hermes wrote above. In the studio, the combination of RX strobes and Skyport RX radio triggers gives you the best of both worlds! I also wouldn't mix brands, it's more trouble than it's worth, IMO.
For location shooting with no AC power, the Ranger system runs rings around the RX strobes, of course. Not only that, it happily co-exists with my RX600 strobes inside the studio, for those time when I need more (or less) power from a light. Instead of having to purchase an RX1200 mono, my Ranger happily punches out 1100Ws when I need it. Instead of purchasing a separate RX300 mono, my Ranger turns down to lower powers than even the RX300... and both my systems accept the same modifiers! 
I'll help you with testing again, Robert!

