With due respect, what's going on 20 years ago is no longer the case today. Extremely rare for a first time MD/PhD applicant to have an R01 in hand while shopping for a faculty position. This however, may not be a bad thing, because depending on the institution, your tenure clock might start a bit later (i.e. when the mentored phase is over). The K series funding rates are also a lot higher. Salary's also not completely tied down to the grant--more related to your rank, amount of clinical revenue etc. In terms of general gestalt for the OP's question, I would say that once you have a promising K, even if it's not fully funded (i.e. in revision etc., but has a good number), your home program would most likely keep you in the cognitive specialties (IM, path, psych, neuro etc.) with a standard salary similar to their usual full time clinical academic faculty. In procedural specialties, you likely could get away getting at least a 50% research position, although sample size here is TINY, and you might be forced to take a pay cut. But multiple people told me that once you have a K you have the option to shop around for things like start-up and ancillary support, other perks, etc. Remember also that there's another steep drop between K and R, with many K funders never move on to R, especially the MD-onlys. LOTS of points of attrition for a physician scientist: MDPhD graduation to residency--if you decide to ditch research, then after residency at fellowship, then after fellowship at K, then after K at R, the after first R at the R renewal, then after the R renewal at the 2nd R (a.k.a. tenure review.). It's a marathon! But things open up. Once you have a K likely there are a panoply of options out there, and once you have a history of an R, you likely not so much "drop out" as moving on to greener pastures (i.e. pharma, $$ private practice etc.)
So I guess the take home message, to me and to you, is to RELAX! and enjoy the ride. Do whatever makes you happy and don't be afraid to take some risks. Yes the salary's lower but it's by no means unlivable. Grants are hard to get, but you'll have help. And if you don't get where you want to be, you can still do private practice and double your salary. THINGS WILL WORK OUT IN THE END. YOU WIN NO MATTER WHAT.
In the basic sciences, which I also know a bit about but isn't personally intimate with, things are a bit different and more egregious, and it's also very rare to have a R01 in hand. In fact it's very rare to have a K in hand, and a lot of times people with good connections and publication records just get tenure track offers, usually with a certain amount of start-up. I think most institutions would prefer to get a US born/trained postdoc from a Nobel/famous person's lab with an enthusiastic endorsement from various chairs and a few nature papers, but no solid funding as yet, than an international applicant who just chanced on a K99 with a solid but not exceptional pub list. This is unfair but seemingly how things are going these days. If you want to play that game I suggest checking out the list of HHMI/Nobel and the related labs in your field that publish routinely in Nature/Science/Cell and go there. You can always chase after your pet dream after you get your lab funded and have some slush fund and a gullible minion. I'm pretty sure that if you do two rounds of postdocs at two Nobel level labs with solid papers, you have 90%+ chance of getting a tenure track job at a respectable major research institution. And don't tell me "oh but he's working on the wrong system," or "oh he doesn't do the technique I want to do..." It's not about that at all. It's the networking and connections. You go to his lab and pitch your idea to him and CONVINCE him to do what you want to do, then BRING IN the techniques you want. If you want to be a PI, you have to think like one. To just roll with my soap box a bit more, this game unfortunately is gratuitous, especially for women in science, because this idea of "pitching" anything is especially alien, but unfortunately it's the way things are going right now. There's just no place in the system for a large number of people who want to get a decent salary and just do science on daily basis, as opposed to devote a career to schmoozing and fighting reviewers.