Actually, I'm very happy with the result.
It a result that even the best analytical chemists would be happy with.
I'll use RSD, for it makes it easy to compare...
RSD of 1.3% is extremely good.
RSD under 2% is good when you are actually just injecting the same exact sample again and again.
Here we are talking two different samples.
5% is average accepted RSD in cases like that.
To verify my claim independently input numbers here:
Relative Standard Deviation Calculator
and check for example this:
In chemical analysis what is the generall accepted %RSD. Is there...
Or google many other references.
Hope I helped.
Cheers