Eric has a good point about the "out of round", that I failed to emphasis, but falls into the 'assembly issues' area.
Most machine shops can get things pretty round - it's the way the machine tools are designed to work normally. The parts really should have been machine right - but, '$hit occurs'. The problems should have found during pre-assembly checks.
According to bearing manufacturers, the majority of bearing failures are caused by installation issues. I worked on many "come-backs" during my wrench-twisting-days that were directly traced to grease,chips,dirt & etc. being trapped between the bearing shell and the block bore (or rod bore)causing the bearing crush to be wrong and the bearing to be deformed at assembly. This type of failure was way more common than the bearing size being wrong. Many of these types of problems will not show up with the standard 'plastic-gauge' checks, only good measurements and assembly technique can prevent them. If you see your machinist/engine builder useing only 'plastic-gauge' during his "blueprinting" of your block - grab everything and leave. IMHO of course.
Long way of saying the 'out of round' is probably on the bearing side of things, not the crank or block bores.
If, as Angel says, 'the guy threw the thing together' and didn't keep every thing clean the problems may be slight - but, only carefull attention to measurements will be able to tell. If that motor already needed rebuilding prior to you getting it - chances are it lead a hard life anyhow, them things aren't all that old yet.
Best of luck with the block - let us know what you find as you tear into it!
ps: Never ran into a problem with bearings being 'to loose' at install and causing a 'spun' bearing - just "hearing loss"
(sorry so long)