1bc1rr,
There are a lot of varibles there. But if you drive the way I do in my Ford f-150, the differance is about 45-60 minuets shorter, going the lake Arrowhead route is faster.
This is the route I take. I turn off the 330 freeway on Waterman road and go to the Lake Arrowhead turn left. About 2 miles there is a stop sign, go right. Follow this route around the Lake into grass valley. If you get to where the road turns to dirt turn around as you have gone about 2 hundred yards past the white wooden bridge. Park near this bridge and go north. There is a fence with a gap about 100 feet from the road and north. Go thru the gap and when you are thru the small valley the path splits. Stay to the left, thru the small trees and stay on the path about 2.8 miles. When you get to deep creek turn right and about 100 yards you will see the hot springs.
Good luck and happy hot springing !
Also please post a trip report with your opinion.