Buying a shed - any tips from your experiences?

We're looking to replace a 6ft x 8ft wooden shed. Lots of researching, but havent had chance to get feedback from people who bought one recently.
Going for the same size. Not going top end (no Tiger Sheds for us, they look grrreat though), ignoring the DIY Barn specials too, looking at some of the mid price suppliers and looking around local specialists this weekend.
We've learnt that:-

• cheaper ones have poor flooring and small framework (25mm ish).
• Slightly better ones have some better timber (38mm ish) but aren't very tall.
• Next level will be sensible height, reasonable framework (50mm ish).
• Now we're at sturdy framework (50-80), decent window, door, roof, floor etc.

Above that is more improvment on the spec, different wood treatments, pressure/ tanalised etc.
A couple have said pressure treating is not required, but couldnt elaborate why (they didnt supply it).

Any recommendations/considerations that you have found out? Any value in paying for pressure treated? Happy to creocote it annually.
All appreciated