As I've never been comfortable with female things, I have actually missed out on a LOT of female privilege that's out there (yes, it does exist).
There is ladies' night at most bars and taverns, and even on the other days of the week, men are very likely to buy drinks for women. All of my female friends get drinks bought for them all the time. Meanwhile, us guys are always stuck with the tab at the end of the night (the only time I've ever had a drink bought for me was when my friends and I went out to the strip club, and the drunk guys next to us bought shots for all of us). Women can get all kinds of free stuff just for being women. There are lots of websites out there that send out free trial items to women, and a lot of other businesses will make offers only available to women (most recently, I've seen signs for a free 30 days of kickboxing lessons). Small businesses can also usually be negotiated with, and the prettier the woman they're talking to, the higher a discount they can receive. It's always rough seeing everything women can get for free, while I'm stuck struggling to pay for things for myself. Not to mention, I'm usually the one women come to to buy them drinks and lend them money and help them out with rides. It's definitely an expensive world being a male, yet at the same time, I've had auto shops try to swindle me and lie to me thinking I'm some dumb female that knows nothing about cars, so maybe in the end it all evens out.
At my work, it's been pretty tough adjusting to privilege switches. As a "female", the male customers would always come in and rave about how pretty all us girls working there were (even though I never looked good, I looked female enough for the customers to group me in with the half-naked girls I work with). Since I've started wearing men's clothes full-time, I no longer have the creepy old men hitting on me, which has its ups and downs. On the downside, I don't get as many (or any) tips from some of the guys who come in (the one guy tips $10 every time, even if his meal only costs $7, but ONLY if the super-slutty girl is there). But on the plus side, the customers seem to have more of an interest in me as an actual person, and are more attentive to our conversations. Also on the downside, I can sometimes be in the middle of a conversation, and then the girl missing half her clothes walks up and they immediately cut off the convo and start talking to her. Also, since I've never been feminine, when the two girls are talking to each other, no matter what I have to say to either of them, they ignore me like I've never said a word.
Being in a sort of in-between state right now, it's hard to really separate the people who are giving me male privilege versus the people who just see me as a non-threatening, down-to-Earth female (it usually seems to depend on if I'm wearing my glasses and how visible my chest is in the shirt I'm wearing that day). I'm hoping once I really get further into this transition, I can notice more and more privilege changes.
As far as manners are concerned, such as holding open doors, I've always done polite things for everyone, but I do always place priority on certain people. When I'm serving people their food, I always try to serve the women first (assuming the food comes out at the same time), or I first serve the elderly or young children. People may not notice small gestures like that, but I've always strongly believed in manners. Being a gentleman always bring me a small dose of self-satisfaction anyway.