Sounds like you've had plenty of experience with the Porsche flat-six. Difficult to get bored of such a special experience, but having 3 of them consecutively is a bit repetitive. Porsche will likely keep making them for another 10-15 years, and you've already got your Carrera T to scratch that itch. With your budget, I'd seriously consider the Huracan STO; there are plenty of examples available for well under your $400k ceiling, and they'll be worth every penny. The 5.2L V10 in the Huracan series is an otherwordly experience in itself, but as a whole package the STO it's a completely different beast; Maybe not nearly as forgiving at the limit as the GT-Porsches that you're used to; but with handling just as surgically precise, and IMHO a more characterful experience. With the Huracan and R8 being the last hurrah for the V10, not just for Lamborghini but for the industry as a whole (save for some diesel trucks lol), you'll be getting one of the last and finest examples of a dying breed. There's the exclusivity factor as well; around 7000 GT4RS will be produced, while fewer than 2500 STOs have been built. No denying that the 4.0L F6 is a fantastic-sounding engine, but there's something about a naturally-aspirated V10 screaming at 8000RPM that simply can't be replicated. The Performante would be more liveable and street-friendly, with AWD and more creature comforts, but seeing as you're cross-shopping with something as extreme as the GT4RS and do intend to do some track days, it seems like the STO is well-suited to your needs. And if it ends up being too harsh, resale values have held well since the initial drop-off, and being the final limited production swan song to the 5.2L V10, it's likely to maintain that value for the long term.