Sorry to hear about your bad luck, Juniperpansy. What a drag. We went up last week for the first time and may have used up all the luck that stretch o' road had in reserve!
We were under the impression that we were slightly crazy to be attempting the trek in our early-90s Toyota Corolla (crazy = confirmed) but we were just so desperate to escape the city we were willing to drive 10km/hr (even SLOWER in some parts!) to get there. The driver played "thread-the-needle" around the potholes the entire way, while I was on "sharp rock alert" duty. There were some parts we could "rev it up" to 40km, but for the most part we were truckin' along under 20km.
Crawling along would have been embarrassing if the beauty of the springs didn't warrant such craziness. The locals and other drivers looked at us with either bewilderment or amusement - we made sure to follow awesome road-etiquette the whole way, and pulled over to wave everyone past us. The only people I felt bad for were the construction workers who have to stop at the top of every hour to let traffic through both ways... nothing like watching ten SUVs/trucks fly by you and then hear over the radio there's a little corolla still picking its way through your section

We definitely plan on travelling in a vehicle with high clearance and good tires our next visit, especially if it's later in fall.
I am so incredibly grateful for the entire experience - I think the "other" forum had a thread where a local resident posted, and I'll head over there to thank her and her community for being so incredibly accommodating towards the endless string of visitors we encountered. I definitely wanted to thank everyone in this forum for filling the gaps in our research (especially for all the pricing info, Bulldozer!) as I'm not sure I would have felt confident venturing out without the personal accounts and updated details.
NOW WHEN DO WE GET TO GO BACK!?!?! =)