Thing wins.Strong Guy has the mutant ability to absorb kinetic energy and use it to enhance his physical strength up to an unmeasured limit. However, he cannot store the energy he absorbs for very long; as a rule he must expend it within 90 seconds to prevent the enormous amounts of energy from permanently distorting his body. He is in constant pain from the existing distortion, although he hides it well, traditionally playing the role of team comedian to distract himself.
An unusual percentage of his body mass is stored in the upper half of his body, causing him to appear top-heavy and thus very imposing. Strong Guy's maximum strength level is such that he has sufficient strength to take on the Hulk, and he is formidable at "street fighting"-style hand-to-hand combat
Strong Guy's one win of any significance was against Blob. He got owned by the Prof Hulk when he had the rest of X-Factor fighting with him. Thing fought an android with the same powers as strong guy built by the Black Panther...figured out its powers in about 2 panels, and then continued to kick its ass until it overloaded with energy. Thing would beat Guido's ass til he explodes.