Helipad approaches don't seem to vary much from type to type for PC1, especially in the last 100' or so, so why would different companies have different criteria?
A Bell 429 goes diagonally for PC1 for a start, an H145 (with the right kit) can do vertical from LDP and an MD902 is far shallower than an EC135. So plenty of variation. And the military don't do PC1 at all. Above 200' there are indeed pretty identical. Below that, not so much.