I won't say anything against the stories per se, because I think that PKJ's Superman Gladiator idea is good (finally something interesting, and well-drawn with Kal-El) and I generally like Mark Russell, but may I say that - once again - it seems like a wasted opportunity?
I mean, I get it - something will be seen in the regular series, 5G was originally a different thing and plans changed - but still, it looks like something that in a different situation could have been used as the basis for a truly epic storyline which could have progressed for two, three years with an equally epic climax. It's the type of story which could have been on the same level with some classic Marvel storylines of the 1980s/1990s. I mean. Lex Luthor terraforming an entire planet and making it his personal kingdom and Superman becoming a slave on a distant world.... I'd read it. Alas, we will get only two, three issues of these stuff and maybe something in the regular series.