200 is a good choice, parts are pretty twisty and all 2 lane... or ya can stay on the 90 about 50 more miles and take 12 to Helena and up 15.. little faster with more interstate, but going thru Helena ... no way would I take 90 all the way to 15... another option is ya want to see some beautiful country is hwy 2 from Spokane up thru Kalispell, past Glacier and on to conrad... all 2 lane