Hi Nick,
As you've noted, finger plates are more common on surviving gothic gauntlets than scaled fingers, although scaled fingers are present on probably the most famous of all gothic armors, the KHM A62 armor (the one Max I gifted to Sigismund of Tirol).
Here's a closeup of A62's left hand:
I don't know that one is necessarily more protective, but they are both very comfortable to wear from a practical standpoint. Gothic
mitten gauntlets are also an option and they are definitely more protective than any type of fingered gauntlet. I've worn earlier style gauntlets with both plated and scaled fingers and they've both felt very good (I would even give a slight edge to the feel of the scaled fingers I wore). Admittedly they were both made by a very competent craftsman. Like you said, getting a 'good enough' fit with scaled fingers is pretty easy since precise measurements are not really necessary other than the general overall length of the finger. Plated fingers need to be pretty darn close to the measurements of your individual finger/knuckle placement or they can cause problems. Most people will be pretty similar in finger proportion but if you have particularly non-standard fingers then you'd really need to make sure the sizes of the individual plates are fit to you.
If the aesthetic is most important to you, choose what you like the look of the most. If protective value is more important than anything else, consider mittens and learn to love the way they look
There are also bifurcated gauntlets, where the two outer and two inner fingers are fused but each pair can move independently, and if you're feeling really daring there are gothic gauntlets with mailed fingers only.
A lot of modern craftsmen do not make scales like historical scales though. They should be very closely overlapped, and they often use compound curvature (they curve not only across the finger but down the length of the finger as well). Real ones are also pretty thick in the center. Real individual finger plates are also pretty thick in the center and drawn out thin by the edges. This is a function of the way they were made and the nature of the starting material. Modern armorers use uniformly thick starting material so it's a little more difficult to achieve the dramatic differentials in thickness that historical armor plates demonstrate.
That was a really long way for me to say "I don't know which is more protective but they're both nice!"
Just a note, the second picture you show also looks like a modern reproduction, albeit a much nicer pair, but modern nonetheless.
