It does make my heart race. The Nikon SP is every bit the equal of a meterless Leica M camera. I bought a user SP for about $850 back in 1990, and for close to 10 years I used it pretty roughly as a professional camera, taking it all over the world and even shattering the big glass front window on assignment in Macedonia (replaced it with some photographic-grade filter plastic). Once you get used to their quirks, these cameras really are among the best ever made.
Since it comes with the excellent 35 1.8 lens, I'd be on the lookout for an 85mm f/2 next. It's a powerful pair of lenses and among Nikon's best ever. It does take a few weeks to get used to the unique finder -- with the 35mm, you focus on the right side, then frame using the built-in mini finder for wides.
It's such a joy to shoot longer lenses with the SP that you might want to get a dirt-cheap 135mm f/3.5. Make sure it's got the black barrel -- much less weight than the chrome. And on any Nikkor RF telephoto, ask the seller to double-check that it's not a 'C' lens with the slightly different Contax mount.
Remember that the SP had a built-in 28mm finder something like a decade and a half before Leica. The 28mms are among the pricier of the user Nikon RF lenses -- in the $300 to 400 range for a chrome one -- and the cheaper chrome version is noticeably heavier. Stephen Gandy's CV 28/3.5 is probably the most lightweight and cost-effective solution, though I do like using 50-year-old glass. There's just something magic about it. I was always puzzled as to why CV didn't offer any glass that would be unique for Nikon RF shooters ... like a 28mm f/1.9 or the 35mm f/1.2 in Nikon S mount. The Nikon can focus fast and long lenses more accurately than a Leica because of the long base-length and 1:1 finder.
Because the camera is so flexible, I tend to shoot it with different combinations of lenses. I particularly like using the 28mm f/3.5 because it's so compact and unobtrusive. True, the focal length seems close to the 35mm, but that SP's finder shows you the significant difference between the two. I tend to carry both the 35 and the 28 ... the 35mm is two stops faster and ideal for low-light shooting while the 28mm gets a bit more use and has nabbed a larger portion of my "keeper" photos. The camera's heft makes slow-speed handholding easy, so I'm often shooting the 28 wide open at 1/15th or 1/30th of a second, and 1/8th isn't impossible either.
FYI, my camera bag usually has either the SP or S3, plus a 28, 35, 50 and either the 105mm as a sole telephoto or else a combo of the 85 and 135. On the other hand, on vacations and traveling light, I've found that a 35 and 135 can be extremely flexible. When weight matters, I'll use those two plus a former-Soviet 50mm and 28mm just to keep those bases covered (the former Soviet Orion 28mm is f/6 and scale focuses with no RF coupling, plus mine fits a bit too snuggly, scratching the front plate of the SP, so it's not recommended at all for an SP-2005).
By all means let us know how you like shooting photos with this gem!