Okay then here's the trip report.
Had only 4 hours of sleep. Woke up at 6:30 am. Left at 7 sharp. Odometer reading, 39,524 km and about 140 km on the trip meter, from the past few days of driving in KL. Four bars remaining = ) Joined PLUS at Sungai Buloh junction. After the Sungai Buloh Hospital junction there was a massive jam, and it wasn't even moving

Thankfully after twenty mins the queue cleared and I saw the police, PLUS Ronda and other people on the left side, couldn't really see what was there but on the right side there was a gaping hole in the divider. Probably from an accident last night.
I cruised at about 110 km/h, reached Tapah R&R just before 9 am. Went for a toilet break, had a sausage bun for breakfast and filled up. Odometer reading then was 39,659 km, which means that I travelled 135 km from PJ to Tapah, and 285 km since the last fuel up. Amount filled was 20.327 litres, giving 7.1L/100km.
Exited at Tapah and got onto the trunk road. For the first 10 km or so the road was empty (no one in front or behind me), and pretty flat too so I just stayed in 5th gear. The first obstacle was a lorry, to my surprise the driver slowed to the side and waved at me to overtake when it was safe. Then later there was a slight queue of three cars, a Dugong going slowly, behind the Dugong a Waja followed by a 6th generation Civic. Then later a Cherry Easter MPV appeared behind me. When it was clear I overtook the Civic and Waja both in one go, then subsequently the Dugong. Surprisingly the Cherry followed suit. I think there were one or two other excavators after that too.
I switched off the air-cond when my GPS showed elevation of about 300 metres.
The stretch between Tapah and Ringlet isn't really steep, I was shifting mainly between third and fourth gear. The first bar of the fuel gauge dropped after about 70 km. This is about the same as my usual city consumption (which is better than most because I seldom get stuck in jams).
The Cherry stayed behind me all the way until Ringlet. After Ringlet the road became busier, but it wasn't so narrow. I drove on, climbing higher and higher until Brinchang, where I stopped somewhere just after Equatorial for a few minutes to stretch my legs. GPS elevation there was 1,616 metres
Pics from my crappy Blackberry 9700 phone:


The Simpang Pulai downhill road was a good drive. You can touch 70-80 km/h quite frequently, I think at one point I went over 100 km/h. There are a few corners where you need to slow down to 40 km/h but those are rare. Look out for the giant [>] or [<] signboard.
Surprisingly both roads were well maintained, fairly smooth and even. There were a few landslide spots but JKR workers were actively working on the site.
Now, about the car. I don't have experience driving other cars on these kind of roads, but subjectively, I thought it did rather well, considering everything's completely stock. Having a manual tranny helps too. It's always good to have total control over your gears. I always complain about the gear ratios being too short, but I guess it's a plus point for uphill driving. As it's my first time on that road I didn't push too hard, but drove at a pace I felt comfortable with.
I was driving alone, with about 30 kg of stuff in the boot. For climbing and overtaking, I felt the engine wasn't underpowered at all, as long as the correct gear is selected. I didn't rev high, about 3,000 RPM gave sufficient torque. There are quite a few things which could be improved, the A pillar really gets in the way during right corners (I had a near miss with a bus because of that), and I've brought this up a few times before, the placement of the accelerator and brake makes it impossible for me to practice heel and toe unless I find a way to raise the accelerator.
So overall it was a very enjoyable drive and I will definitely be going back again soon.
At Simpang Pulai I joined the highway again for a short stretch to Ipoh. Picked my friend for lunch and then we both went back to Penang, and finally:

(My apologies for the quality)
Final odometer reading today is 40,020 km, which means I've driven a total of 496 km today.