Duplicator 6 - Layer bonding in thin walls - are my expectations of ABS too high?

I just recently started printing with ABS. I need various parts for my racing quadcopter and since I wanted to print parts that are strong, I decided to try ABS. But I have a problem with thin walls, and I'm not sure if the walls in the model simply are too thin, or if it's me that can't get the settings right.

I have tried to print the following model (from http://www.thingiverse.com/thing:1644765):

Attachment 10448

The distance between mount holes is 30.5mm and the walls are about 1mm thick.

I print with a Wanhao Duplicator 6 (also rebranded as "Monoprice Maker Ultimate 3d printer") with enclosure. I have tried various combinations of the following settings:

* Layer resolution: 0.04, 0.08, 0.12, 0.16, 0.20, 0.24
* Print speed: 20mm, 30mm, 40mm, 50mm, 60mm
* Temp: 230, 235, 240, 245, 250, 255 degrees
* Bed temp: 50-115 degrees
* Fan: Off
* Distance between nozzle - bed: Various distances

While the main plate itself is VERY strong, I have severe problems making the thinner walls strong. The different settings absolutely do affect layer bonding, that's for sure. But the walls in the model still break when I apply force, the layer adhesion breaks with a snap.

Are my expectations of ABS are too high? If so, is there another filament better suited for finer prints that need to be strong? PETG?
Are the walls in the model simply too thin to be durable? I don't expect the walls to be able to take a severe beating, but I'd like the walls to bend instead of snap and break. Is that even possible?
Can budget filament be the cause? I use a fresh roll of LuxorParts ABS that I could get fairly cheap in a local store.

I could of course make my own model, with thicker walls. But that would leave this question hanging over me. So before I move on, I'd like to know why my expectations doesn't meet reality.