Ultimately using monolights with a battery pack is less expensive and less work overall.
A Vivitar 285HV is about $100, Stand $30, umbrella adapter $15. I believe a set of Eneloops with a recharger is $20 for 4, $10 without the charger. I have 2 chargers for 6 sets.
So 3 lights would cost $515 for lights and batteries. Even if you went with the
Adorama flash points and a Vagabond II (which I'd recommend a Tronix Explorer over for build quality), you're paying $500 for two lights, stands umbrellas, and a battery.
With that there's also a lot larger gear and more weight that has to be carried. I fit three speed lights and 5 pocket Wizards among my main camera bag and a second small camera bag that's probably about a 1/3 of the size of my 7MDH. To take 3 heads, a 400w/s pack (which is absolutely tiny compare to a normal size pack), stands, modifiers, and a battery, I'm using a rolling luggage case and other bags. That's also a ton of weight.
I'm pretty sure most people can guess what I'd rather carry if I had to walk 1/2 mile to 1 mile to shoot location, or if I was shooting in a space where I didn't require a ton of light.
I wouldn't necessarily classify monolights as a less expensive and easier option. It totally depends on what the person is shooting and where they're shooting it at. If the OP wants to shoot cars or a lot of outdoor portraits where having the ability to bring down the ambient is essential to him, I wouldn't recommend speedlights. Then again, I also wouldn't recommend 160w/s monolights as they're not going to have the power he needs.
OP - What are you shooting? I was shooting outside with one head on a 400w/s pack with a beauty dish and was still having problems over powering the sun.