>>1740155here, have some data from my usual rides to the hill, up it, down it and back. I'm no athlete, I'm actually obese by BMI. anyway, your questions.
1. I didn't ride with it that light for long as I put a kilo of rack on the back but yeah, the steering is way more lively. hard for me as a beginner to attribute this purely to weight as the rigid fork is very slightly taller A-C than the locked out height of the other fork (10mm or so). the steering will do its own thing now much more if I ride no handed and don't correct it.
2. yes I ride trails on it. I am not a DH bro and I only ride green trails so my insight may not be relevant for you but it climbs fucking great, it's more comfortable than a locked out fork, doesn't bob while climbing like an unlocked fork and I'm dragging less weight over each obstacle. downhill I actually prefer it too, it's very predictable over gravel etc. it fucking sucks for rock gardens. yes, worse than that.
>>1740160based fellow traveller