Didn't have any problems with it for six month/2.5k.
Weak oils generally won't show problems that early - unless you removed the top of the engine before you installed the oil & did visual/tool readings -- then did it again after you quit using the el-cheapo oil.
Most oils nowadays are serviceable short-term. You normally won't notice a difference in 6 months/2.5K.... buy may notice things like cam marks after two years/10K. What you may notice short-term is a difference in internal engine sound. However, even good oils like Mobil 1, Valvoline... etc... can change the 'sing' in your engine.