I never heard of triangles being a problem in ANY application, when used intelligently,  because all 3D apps "see" quads as triangles in the end.  Ngons are the big no no for professionals, not a triangle here and there.  I think any pro knows that Ngons are the debated topic.  In fact, there was a very interesting debate about it over in the modelling forum on this website not long ago, and good points were made for both sides, but the fact that ngons get triangulated in unpredictable ways sometimes, and the problems they present in texturing and deformations is the issue.  Tris aren't bad, when they are placed on flat surfaces, or in areas where they make sense because of edge flow.

---

Tools :  3dsmax 2015, Daz Studio 4.6, PoserPro 2012, Blender v2.74

System: Pentium QuadCore i7, under Win 8, GeForce GTX 780 / 2GB GPU.