So my situation is that my fiancé and I will have been together for ~5.5 years when we get married in a few months, when we'll both be 25. Met & started dating sophomore year in college, then dated long distance for 1.5 years (for a few months before that, he lived with me, then a few months after that, I lived with him before moving to a third city for grad school). Now, with the first year of my PhD over, he's moved to be with me and we just moved into our new rented apartment together.
We are coming in with similar assets - I have about 47K in a Roth IRA, he has about 40K. I completely believe in total melding of finances, I needed to feel comfortable doing that to feel comfortable getting married (and I am wicked protective of my assets, so it means a lot to me to have found someone I will be sharing all finances with). The plan is to use one of my CCs with him added to the account as our joint account, as well as my bank savings/checking account (as only I currently have direct deposit set up, he *just* got a job in the new city, yay). Then all our individual cards we'll probably keep, setting up auto bill pay and some. Low recurring expense like netflix or whatnot. So everything will be joint, maxing out his 401K, both Roths, saving tons. The goal is to mostly get by on my 31K stipend, and save his ~55K salary.
It's been a bit hard emotionally on me to have effectively joint finances while he was unemployed and I was hardcore working/struggling in school, which I didn't expect. But there's no competition, no score-keeping in the long run. If I become a tenure-track professor, I would be making 150K reasonably, so then I'd be the higher earner, but then again, it's also really impossible to predict the future, we're so young. Academia could not work out, or I could pursue something different, plus he has a lot of potential earnings as a chemical engineer. And I view us as a team - if I make the money but he moves for me/my career, his lower earnings don't make him any less of an equal in our relationship/finances.
Good luck! (I guess I should add that this works because we are both reasonable, responsible, not crazy consumer people. We have different spending proclivities (he's much better at cooking/eating at home, but has the car/gas/insurance costs, whereas I care more about traveling a lot, yet spend more on clothes (since he spends nothing)). But it's all wonderful, I trust him, I want to be accountable to him.