Apologies in advance, I know it's my Hobby Horse, but can I suggest again that engineers shouldn't use words like 'accurate', 'decent', 'nice' or 'quality' because they are meaningless in the absence of a specification.
Factors that help choose a spanner set include:
- Cost (Very cheap and unnecessarily expensive tools both waste money.)
- Fit (Only likely to be a problem with very cheap spanners.)
- Strength. (Drop Forged should be strong enough to shear ordinary bolts and special steels are probably unnecessary for small spanners.)
- Need for Slim-line or Obstruction features, rings, etc. (This is why I buy them.)
- Comfort. (Only important when spanner are much used, and is individual. You might prefer Facom to Snap-On or vice versa. )
- Required life (40 years full-time abuse in a garage or occasional use by a gentleman hobbyist.)
- Pride of Ownership or Bragging rights important?
What do you get from an expensive spanner? They stand up better to hard work, feel good in the hand, and being slimmer may be easier to get into tight spaces than equally strong but clunky inexpensive tools. Otherwise they're not magic and don't tighten and undo ordinary nuts and bolts any better than ordinary spanners. (Jammed and awkward to get at nuts and bolts are a different story.)
Buying tools, I always ask "what's this for?". Sometimes the answer has me spending more money, more often I spend less, releasing cash for other pleasures. Although my tools are mostly unloved, it's a hobby I happily indulge, and I understand why chaps desire 'good' equipment. Be honest though – is it a tool or a toy?

Dave