To answer your question: That depends. If there has been recent rain (not snow melt) the Kings tends to color until the runoff reduces. Once the runoff ceases, the river is only marginally more colored than the White. Of course the gully washers of the last two Springs colored the White as well as the Kings.
Personally, I don't like to fish cold, dirty water - never have done much good - so in the Spring I'll head where the water is clearer.
Can't speak for lower lake - it has been many years since I fished down there - but early March offers options at the upper end. The winter walleye run above Beaver doesn't end until the last part of the month. The jerk bait fishing in the Eagle Rock to Big M section is outstanding, and places like Butler Creek, Owl Creek, Panther Creek, and Rock Creek offer some good blade bait fishing from time to time. Best of all, the water up here is outstanding wiggle wart territory.
If I had the money I'd hire someone to show me that section of the lake on the first day.