ill stick to my iron-on's ty.
nah jk but srsly there are far more popular methods than these 2.
i prefer hand made screen prints myself, lets you know someone really put work into it.
There aren't too many processes actually. Maybe 5-6 ways. The only ones I'm familiar with are:
DTG (Direct to garment)
iron-on (this is crap)
He is asking about which inks are better to use, not process. He is most likely going to use screen printing (assuming that he wants optimal quality). Screen printing has a list of inks you can use including plastisol and discharge. You are right about the "lets you know someone really put work into it". It's a very annoying... long... tedious process and in the end... if you eff'd up somewhere... it's frustrating. However, if in the end, you get it right... it's like the greatest feeling of accomplishment.