Well, I went through with it, taking a character with Heavy Weapons and Mecha Gunnery. I got the serum relatively early (somewhere around day 2 or so), so I didn't have to spend much time tooling around with low physical stats. That said, I went with Pe 15, Cr 15, Eg 11, and two sniper rifles. I'm bad at dodging, both in a mecha and on foot, but as long as I take out my enemies at long range, it's no problem. And at low-renown levels, it's easy to take out my enemies. (Though that didn't stop me from getting head-shotted on my first time into the Mecha Sporch arena...) It took about 8 days for the serum to finish working its way on me.