so ive been running an RTL-SDR v3 with SDR# for maybe eight or nine months now and honestly its been pretty great for getting into this stuff. mostly doing wide scan monitoring, some aircraft stuff with dump1090, and occasionally trying to pull in some HF with the direct sampling mode. the HF direct sampling thing works but its... rough. lots of noise, images all over the place, and anything below like 5 MHz is kind of a mess unless conditions are really good.

anyway i keep seeing people talk up the SDRplay RSP1A and the price point isnt insane, its what, $110 or so. supposedly the front end is way better and the 12-bit ADC makes a difference on crowded bands. but then i also see people saying just get a HackRF if you want to actually transmit eventually. i dont really care about transmitting right now, just want better receive performance especially on HF.

has anyone actually compared the two side by side or made this jump? wondering if its worth it or if im just chasing marginal gains and should spend that money on a better antenna instead

I made almost exactly this jump about two years ago. Had the RTL-SDR v3, was doing the same thing with direct sampling, and yeah the HF experience is just kind of tolerable at best. The RSP1A is a noticeable step up for receive, no question. The dynamic range difference is real, especially if you're anywhere near AM broadcast stations — with the RTL the front end just gets hammered and you get all kinds of crud bleeding into adjacent frequencies. The RSP1A handles that a lot better with the built-in preselectors.

SDRuno is fine but I actually ended up running the RSP1A through SDR# with the SDRplay plugin and that worked really well for a while before I switched to SDR Console. If you're not planning to transmit then the HackRF doesn't really make sense for this use case — it's a 8-bit ADC and the noise figure is worse than the RSP1A for pure receive work. the HackRF is more of a do-everything device and it compromises some on receiver quality to get there.

spend the money on the RSP1A before the antenna honestly. a better receiver shows you what your current antenna is actually doing and then you can make a smarter decision about the antenna after.

dont sleep on just adding an upconverter to the RTL-SDR if budget is tight. the ham-it-up or even the cheaper clones do make the HF situation a lot less painful. thats not me saying dont get the RSP1A, just saying theres a cheaper middle step if you want to try it. i ran that combo for like a year before i moved to an Airspy HF+ Discovery which is kinda a different beast anyway and overkill for most stuff