Minimal or Professional for formal work
If most of your invoices go to businesses, or you're VAT registered and want a classic, ruled layout, Minimal or Professional read as immediately credible and are easy to scan for the figures that matter.
Modern or Bold for a stronger brand presence
If your business has a strong visual identity - a distinctive logo or brand colour - Modern's header band and Bold's dark summary panel put that front and centre without sacrificing legibility.