Isn't a Barlow lens pretty much the same as a Premier Reticle booster for Leupolds?
A higher quality lens would normally have a low Cs (spherical aberration coefficient). Just having a large objective lens doesn't mean it will give a wider field of view or better quality if the manufacturer puts in an aperture to use a narrower angular acceptance.
A better lens, for me, simply means far less eye strain over a long event. A cheaper lens leads to more errors.
However, my background in in electron microscopy and where high resolution was measured in angstroms (0.1 nanometres) and the image "focus" is one of many as you play with recombination of the reciprocal lattice :-)