I am glad you're happy with the GD77s, but if you really want to see mind-blowing performance then you should get yourself a pair of XPR7550e and see...
Also, if you are using the GD77s on DMR then it is not legal. GMRS is FM ONLY. Also, to be 100% compliant then you should be using 20 kHz wideband, and because I know that the GD77s won't do 20 kHz, then you should be using 12.5 kHz instead. If you're using 25 kHz then it is not legal either.
You speak like people here in the forum don't know what they are talking about, they are called CCR for a reason. Don't mislead people, dude, grocery store could be 1/2 miles away from home. That is hardly mind-blowing. One radio sitting on a 10 floor building to ground level, not really mind blowing either. I've reached 30 miles using a 2W VHF MURS Ritron portable... does that mean the performance was mind-blowing? Certainly not, why? b/c the receiving radio (a TYT8000E with crossband repeat) was strapped to a drone flying some hundred feet up in the air in the middle of nowhere.
Also, for the GD77S, at 75 dollars a pop you are being ripped off, man. If you want cheap, try the Baofeng DM-V1, which is basically a GD77s, except its 25-29 dollars a pop. The DM-V1 will also do DMR if you really want to have DMR (not legal in GMRS). Then there is the Baofeng BF-1801, 45 dollars a pop and its a GD77 clone, with a REAL screen. However, at the price you paid for those overpriced CCRs you could've bought a TYT MD380 UHF (single band, not the dual band), with a color screen and, IIRC a real superheterodyne receiver too... and have a better than mind-blowing performance over the GD77S... I think paying 77 bucks for a CCR without a screen is a ripoff, fortunately tho, it is great to know that, at least, the performance is mind-blowing. You could've achieved the same kind of mind-blowing performance with a pair of BF-888S, except for 18 dollars, and have enough cash left to purchase a used Vertex Standard EVX-531 on eBay, maybe 2 if you look hard enough.(since you seem to like no-screen DMR capable radios)
Also, I didn't make this post b/c I am brand name snob that just wants to bash on CCRs for the heck of it, so, without further delay let me introduce you to my extensive CCR collection, and the reason why I made this post.
-15 BF-888S, yep, at 9 dollars a piece, they work great for my house intercom, and if anybody destroys one, guests kids, anybody, be it by throwing it the toilet, smashing it with a hammer, etc, etc, won't be crying over it. Receiver on those is BETTER than the GD77s.
-10 Baofeng BF-1801, basically a GD77 clone. Those work great as intercoms on both DMR and FM with the signaling stuff.
-5 Baofeng DM-V1 (which is basically a GD77s, but UHF only, can be modded to do VHF, but haven't tried to do that) Great for store floor intercom, and at 25-29 bucks a pop, its hard to argue with that.
-4 Alinco DJ-MD5 DMR/GPS. Not exactly a CCR at 189 a piece, but these are usually our carry around radios, one for each member of the family (old enough to use a radio) Good balance between features and RF performance, for the price, of course.
-4 TYT 8000E.
-1 Anytone INSTG8R
Forgot to state what I no longer own but that was also extensively tested.
-1 Retevis RT52, one of the worst, if not the worst radio front end I've ever benched, returned.
-3 Anytone 878UV. Too big, I liked the Alinco MD5 beter, returned them all.
-2 UV-5R. All dead.
-2 UV-82. Gave them to friends.
-2 UV-3R. All dead.
-Ailunce HD1. Very poor performance, returned.
I've tested all these radios in nearly every possible scenario you can think of, with several types of ducks, high gain antena, etc, and with the exception of the Alinco DJ-MD5/Anytone 878 (which seems to have better front-end filtering that all those CCRs) none of these radios can compete in terms of range and overall performance to my commercial grade gear, especially when operated in crowded RF areas, which is pretty much anywhere where computers operate these days. Inside a mall the difference is night and day.
Believe it or not, the GD-77S is my favorite radio at the moment. It solves practical problems by slinging squiggles, and it's even type-accepted as a business radio (No FPP). As such, it qualifies as the "surplus commercial equipment" that the 2017 memorandum stated was never intended to be banished from the GMRS, and I believe it's legal under the latest regulations.
And at five watts, it's my most powerful cheap squiggle-slinger. Used with Motorola gear (2W) on both high and low (1W), it's absolutely comprehensible in two directions when cell phones aren't getting enough signal to send a text message.
Is it "good"? Apparently not. Is it good enough? For me and those like me, yeah it is. (And if it gets dropped, I didn't just break irreplaceable hardware!)
Edited to add: And at 5w back and forth, it'll reach from handie to handie all the way to our grocery store, and inside too. As far as I'm concerned, that performance is mind-blowing.