Expected temp ranges for X220 tablet?

I decided to reseat the heatsink on my X220t this weekend with Arctic MX-4.

Idle temp:
Before: 50C, 30 above ambient
After: 45-50C, 20-25 above ambient

30% load temp:
Before: 60C, 40 above ambient
After: 60C, 35 above ambient

(Ambient temps increased in the time it took to reseat the heatsink)

These results seem... poor, possibly because I did not quite apply the thermal paste right--small grain of rice in the middle, but the rectangular rather than square contact surface suggests...

Expected temp ranges for X220 tablet?

Expected temp ranges for X220 tablet?