Questions between T14 and T14s and its generations...

So I'm deciding which to get, a T14 or a T14s. There were already a lot of reviews on the internet, I know, but I just wanna get an updated opinion for 2025.

What I'm getting:

  • 32GB of RAM
  • At least 250GB of storage
  • AMD variant with at least hexacore

Differences I could find between T14/s:

  • The T14 is heavier.
  • The T14 has less battery life.
  • The T14 has dual fans.
  • The T14s has better quality build. (I don't really know what does this mean, let alone knowing what materials it uses does)
  • The T14s has soldered RAM.

The most important factors for me would be:

  • Performance: Would the T14 really be better for performance since it has dual fans? How does it differ from the T14s having just a single fan? Is it really that big of a difference?
  • Battery life: How big of a difference is exactly 50wh (T14) and 57wh (T14s)?
  • Longevity: How long the laptop would last on me. Would the performance still last for several years? Would it have sudden breakages? (I don't usually bring my laptop anywhere and obviously, I don't abuse it. Just saying in case this info helps)

What I do:

  • Android development (or just software developing in general)
  • Web development
  • Gaming (like retro games or GOG, that's mostly what I play)
  • 3D editing (Blender)
  • I use Linux

Now for the questions:

  • What do generations mean? I don't really see much of a difference except that it offers a new CPU. Do they matter? Does G1 have something better than the G2 or vice versa? What do I need to know in this matter?
  • Should I choose T14 or T14s? Would T14 have problems than T14s and vice versa? (like weight and the number of ports but I don't care about the weight and I've already checked the ports and they are just right for my use)
  • If my budget can reach the octa-core variants of whatever I pick, is it gonna be better? I mean obviously it's gonna be better just by seeing the cores/threads it has but I wonder if it would have thermal issues.

My budget can reach until G2 of the T14/s, but if getting later generations would be worth it, I would try increasing my budget.