Full disclosure: I was a play-tester on this, 10 years ago
I've been a Fighting Fantasy ('FF') fan for some 35 years, since I stumbled across 'Forest of Doom' in my local council library. I bought, played and enjoyed the original FF gamebooks as well as both the 80s and 90s RPG version, even as I recognised their weaknesses (wildly imbalanced, poorly suited to long term play).
This (thus far) latest iteration of the rules makes a good effort to address the core weaknesses of the earlier versions but is not without flaws of its own. Some of these are stylistic - the writing lacks the whimsical energy of 'Dungeoneer!' - and some are unfortunately functional. There's an unnecessary amount of detail wedged in, in some cases (you're a rules-light RPG, you don't need a table of over 15 modifiers to climbing checks!), and it's frequently very disorganised. If there is any rhyme or reason to the ordering of sorcery spells or priestly powers, for instance, it escapes me.
There's a solid core here, but it needs more work. I'd love to see a properly re-organised, genuinely rules-light re-write that preserves the whimsy of the original books while better embracing the changes needed when shifting from solo gamebook to tabletop RPG.