Hi bro, that depends on which type of ribbons you buy.
The ones we bought from Hungary does not need T-irons, as its totally based on pressure. Some cellotape is needed to align the ribbon.
Those China ones, which most will need a T-iron, I'll say don't bother. I've seen the material they used. I've repaired a few clusters that uses those and failed after 6 months. They needed re-doing again.
MID ribbons are really hard to get right. I try to avoid doing them, clusters are much more easier to do.