Image-Line recommends using the version that matches your 3rd party VST plugins (32-bit plugins in the 32-bit host) to avoid performance issues with "bridging".
The Producer Edition provides "the highest level of core functions," including:
Version 12 introduced a vectorized, scalable UI, allowing it to look sharp on high-resolution displays through the FL64 (scaled).exe option. Legacy Note & Lifetime Updates
FL Studio 12 was the first version to feature the fully redesigned, scalable vector interface. While 12.1.2 is an older release, Image-Line's Lifetime Free Updates policy means users who owned this version can update to the latest version of FL Studio (currently FL Studio 24/2024) at no additional cost. FL Studio Pricing & Editions – From $99 | Image-Line