In my experience, picking the right street prime is all about finding that sweet spot between focal length and AF reliability. I've tried many setups on my GX85 over the years, and honestly, you gotta be careful with older glass if speed is your priority. Here's how I see the current budget-friendly options for your situation: • Olympus M.Zuiko Digital 17mm f/1.8 - This is probably your safest bet. It sits right between 15mm and 20mm, giving you a 34mm equivalent that works perfectly for busy sidewalks. You can find them used for about $250-$300. The AF is snappy, and that manual focus clutch is lowkey a lifesaver for zone focusing. • Sigma 19mm f/2.8 DN Art - If you’re on a tight budget, this one is usually under $150 used. It’s super reliable and sharp, tho the f/2.8 might struggle in low light compared to the Leica. • Panasonic Leica DG Summilux 15mm f/1.7 ASPH - This is the high-end choice ($400+ used). It has amazing character, but it might feel a bit too wide if you're worried about your shots getting messy. Tbh, the 17mm is the best balance of speed and price. Idk if I'd gamble on the slower pancakes for fast candid stuff!! Good luck.

For your situation, skip the Panasonic Lumix G 20mm f/1.7 II ASPH cuz the AF is sooo slow. 1. Panasonic Lumix G 14mm f/2.5 II ASPH - cheap used (around $150) and *super* tiny.
2. Panasonic Lumix G 25mm f/1.7 ASPH - basically free (around $149) and very snappy. I think that 14mm is clutch for busy sidewalks if ur on a budget. gl!

tbh, I’m gonna have to respectfully disagree with the idea that you *must* stick to Panasonic lenses just because you're on a GX85. I've spent way too much time looking at market comparisons and user reviews, and honestly, the third-party scene is reallyyy strong right now if you don't mind a slightly larger setup. If you're after that perfect balance of speed and character, you should definitely check out some options that aren't the "usual suspects": - Sigma 16mm f/1.4 DC DN Contemporary - This gives you a 32mm equivalent. It's definitely chunkier, but the AF is super snappy and the sharpness is on another level compared to the older pancakes.
- Olympus M.Zuiko Digital ED 12mm f/2.0 - If you're worried about busy sidewalks, this 24mm equivalent is basically perfect for getting everything in frame without having to back up into traffic. I'm still kinda experimenting myself, but from a market research perspective, the Sigma glass offers way better contrast for the money. It might feel a bit front-heavy on a tiny GX85 - which is a downside for that "discreet" look - but the actual rendering is so much more modern. Just a different way to look at it before you settle on the standard choices!

ngl I have been dealing with this exact same headache for about a month now and it is so frustrating. The GX85 performs so well overall and I am super happy with the body itself, but finding that perfect street prime that actually plays nice with the DFD tech is tough. Weeks of looking at technical motor specs and AF cycle benchmarks still havent given me a clear winner. I even tried messing with the custom focus settings and limiters to see if I could force some better results, but I am still totally stuck. It is a bummer that there isnt a more obvious answer for us even after all this digging through the data... glad I am not the only one feeling this way.

I've been shooting with the GX85 for a long time now and honestly, you have to try the Panasonic Lumix G 42.5mm f/1.7 ASPH POWER OIS! I know people usually say go wide for street stuff, but I love how this lens lets me grab amazing candid shots from across the pavement without being spotted. It is seriously fast and the stabilization works like a dream with the camera body! Another fantastic option is the Sigma 30mm f/1.4 DC DN Contemporary. It is a little bigger than a tiny pancake lens but the character you get is just incredible for the price. Quick tip: if you're worried about things being too tight, just take two steps back and let the snappy autofocus do the heavy lifting. It's way more fun than stressing over focal lengths, and the results are honestly beautiful!

the way panasonic and olympus handle their glass is such a headache. youd think after all these years theyd make the af play nice together but nope. its honestly a scam how you lose the best features of your gx85 if you dont stick to one brand. drives me crazy that i have to choose between a lens i love and a body that actually functions properly.

• panasonic lenses are the only way to get decent af on your body
• olympus glass is great but the lack of dual is and slower focus on panny bodies is a joke
• third party stuff is usually huge and ruins the portability i am curious though... how much of your shooting is actually done in low light where you need that f1.7 or f1.8? and are you strictly looking for something that fits in a jacket pocket or is a bit of bulk okay?

For your situation, I'd suggest sticking with any of the modern Panasonic primes. They play way better with the GX85's autofocus than anything else. If you're worried about budget, just hit up the used market and grab their faster lenses... you'll save a ton of cash and still get that snappy performance ur after for street stuff. Just be careful with the older glass cuz it can be slow! What's ur budget looking like?