I'm surprised people still use tripmines after the incendiary buff. I never looked back. I also never used tripmines like they were intended to be used either. I'd just try to get them to explode right next to a person immediately.
Well there's your problem isn't it. LOL
Both incendiary and tripmines are good, with different utilities.
As a lifelong tripmine user, there simply is no substitute.
edit: I present to you, exhibit A, an old gif of mine: