I've never tried to book through Spirit Incentives to utilize PPE companion awards BECAUSE I keep hearing and reading about how terrible they are. I agree that Citi should reconsider who they use.
American Express platinum card members (not from Citi) have MUCH more success booking companion award tickets. However, the annual fee is $450 so you have to know if that is worth it for you or not - a couple of companion tickets should cover it.