Hi JC, and welcome to the site! Google shows MANY complaints of WiFi connections dropping out in Linux, and there are also MANY different solutions. If you want to explore troubleshooting your particular problem, it may take a fair amount of time to weed through various attempts until the correct fix is found. And we'd have to start with learning more about your system... which version of Mint, which desktop, what brand and model computer, etc And we'd have to get detailed information via the command line to find out exactly what Ralink dongle you have... not just the model you may see printed on it, but how Linux sees it when it's plugged in. Many of these devices use chipsets from other manufacturers, so Linux may see it as something other than Ralink. You might get lucky and solve it quickly, or it may be a long tedious process in which several of us on here will try to assist you.
Or, as an alternative you also asked.... is there a "sure-fire device that will work?" I cannot promise that you will get the same results as me, but I have purchased this dongle,
TP-Link TL-WN722N in small batches (3 or 4 at a time) on several occasions so that I always have one as a spare while I give the others away to friends with similar problems with Linux WiFi. This has worked extremely reliably with Linux on many different computers. It's a little bit large and clunky, but the extra antenna size gives it far better range, and poor range can be just one of the many causes of your problem. So again, I can't promise you the same results, but this has been my go-to dongle for quite awhile.
Also note that I recommend the TL-WN722N model
ONLY! This has been basically plug-and-play for me with Linux, but others have told me that Windows may need to search out an updated driver (a Windows driver disk is included, so I don't know why it may not work). I don't use Windows enough to make a judgment on this. The link above shows other more modern versions of this dongle.... and I
do not recommend them. I've tried the AC600 model and I won't buy another.... not for Linux.
So, if you want to troubleshoot... let us know some of the initial details I mentioned above, and then we'll come back with some command line queries for you to dig a little deeper.
Cheers