I agree with the statement regarding the MTH tires being better.
Just for reference, the Lionel traction tire P/N 6308071206 has P/N 6101207206 listed as an alternative.
The P/N 6308071206 is 1.00" ID x .046" TH x .118" WD. (out of stock)
The P/N 6101207206 is 1.00" ID x .050" TH x .118" WD. (in stock currently at the Lionel Parts website)
The MTH tires I have are ~1" ID x .056" TH x .123" WD
Probable will not matter, but at least you now have the information.