[Rathji]

Endo steel is definitely worth it, Ferro fibrous is not quite as worthwhile, as it noticably increases your repair bill, so make sure you are good with the mech you are in before committing.

As for tonnage it will free up. Standard Internal Structure is 10% of your weight, so 3.5 tons on a 35 ton Jenner. Endosteel is 5%, so 1.75 tons (probably rounded up to 1.8). So that is easy to calculate.

Ferro Fibbrous is a bit harder, but only because the amount of armor you have is variable on a mech, and not dependant upon the tonnage. It packs more armor points into the same tonnage. So if you have 320 points of armor (10 tons) of armor, it becomes 12% lighter, so that 320 points would only weigh 8.8 tons. Of course, the end result is you can't really do anything with .2 tons, so you just add that in additional armor points, and gain 1 ton. (or shed .8 tons of armor, and add 2 tons).

Hope that makes sense.

I just finished my second mech, a Jenner, as I sold my Cicada when I was really frustrated with the armament I could loadout (due to me buying the wrong variant). I am in the same boat as you, do I pick up another Jenner and try for the elite perks?

Really, it doesn't take much play time to gain the exp, I was off sick yesterday and managed to finish the Jenner completely in about about 6-8 hours of playtime. It takes a couple hours to earn a million c-bills, on the conservative side, so in that time you could easily make enough to purchase another variant, not counting upgrades etc.