Doing the BoS quest for McNamara in New Vegas. He gives you 3 tedious missions to go fetch stuff across the Mojave for him, and everytime you have to make the annoying walk from Hidden Valley through the entire BoS bunker with two seperate loading screens. Unlike siding with Hardin, you can’t preemptively get everything done before going to the BoS bunker. If you want Power Armor training, you have to repeat yet another journey in and out of the bunker to plant the device on Black Mountain. All of this McNamara makes you do for the privilege of you not having to massacre the Mojave chapter of the BoS when you side with the NCR, but the Mojave chapter has no redeeming qualities whatsoever to make this worth your time. At least with Hardin, you can preemptively get the holotapes and kill everyone at the Silver Rush before going to Hidden Valley, allowing you to easily complete the quest and get Power Armor training before you massacre them all with your shiny new Power Armor