I really like the simple trainer from watching youtubers but I have three questions that may help me to decide.

Question 1
As I look at all the mods they seem to mention Menyoo. Menyoo is even a tag in the filter on this site. I'm not involved in any other GTA forums so maybe this site is bias for some reason? Or is it that Menyoo really is superior and supported more by moders?

Question 2
Is it at all possible to use multiple trainers?

Question 3
Are any of the well known and robust trainers open source? I have some programming knowledge so that would be fun.

If you can answer any of these questions it would make me and my sons day. Thank you very much