Nikkor 24mm 1:2 OR Nikkor 24mm 1:2.8 -- BUT: Heavily Used!

[Sumarongi]

Both lenses now at hand. 🙂
As many of you have pointed out, they're in fact quite different; stats from http://www.photosynthesis.co.nz/nikon/lenses.html

Ser# 236xxx
TypeLens Ai–S 24/2
Serial*No 200001–247547
Date Oct 1981–Dec 2005
Optic 11/10
Angle 84°
Bl 7
Close Focus 0.3
Macro 1:8.6
Focus Throw 80°
Filter 52
Diam 63
Length 51.5
Weight 300
Hood HK–2

Ser#679xxx
TypeLens Ai 24/2.8
Serial*No 525001–684524
Date Jan 1977–Sep 1981
Notes
Optic 9/9
Angle 84°
Bl 7
Close Focus 0.3
Macro 1:8.8
Focus Throw 160°
Filter 52
Diam 63.5
Length 46
Weight 270
Hood HN–1

I'm glad I've bought both: the slower one — having the long focus throw — is IMHO the better one for my daughter, the other one is for me (via adapter).