Every few weeks I get some version of the same message: "I'm about to buy a printer, what filament should I get?" It's a fair question, and it's also the wrong question, because the honest answer is "it depends on what you're making." After two years of running a Flashforge Adventurer 5M Pro and a Bambu Lab A1 with the AMS side by side, I've landed on a working answer I actually trust. Here's the real breakdown — not a spec sheet copy-paste, but what I've seen happen on my own build plates.
Why "best filament" is the wrong question
PLA, PETG, ABS, and ASA aren't ranked best to worst. They're tools, and the job decides the tool. A phone stand and a truck bumper mount are not the same project, even if they're the same size. Before you pick a filament, ask three things: will this part sit outside or near heat, does it need to flex or take an impact, and do you actually have the gear (enclosure, ventilation, a dry box) to print it well. That last one trips up more people than the plastic itself.
PLA / PLA+: the default for a reason
PLA is where almost everyone starts, and for most indoor, decorative, low-stress parts, it's still where I end up too. It prints at lower temperatures, barely warps, holds fine detail, and on a CoreXY machine like the Adventurer 5M Pro or the A1 it runs fast without drama. The catch is heat tolerance — leave a PLA part in a hot car or near a sunny window and it will slump. I reach for a "Tough" or "Pro" PLA+ blend specifically for anything that needs to survive being dropped, like brackets, organizer parts, or anything a kid is going to handle. American Filament's Tough Pro PLA+ is the one I keep loaded most often — it's made in the USA on NatureWorks Ingeo resin, and the impact resistance is noticeably better than standard PLA+ without giving up the easy print behavior.
Good for
Figures, organizers, brackets that stay indoors, prototypes, anything multicolor through the AMS.
PETG: the bridge material
PETG is what I reach for when a part needs to survive outside a climate-controlled room but I still want an easy print. It's tougher than PLA, handles more heat before it deforms, and has decent outdoor life — think garden tool handles, enclosures that sit in a garage, or anything that might get rained on briefly. The tradeoff is that PETG strings more than PLA if your retraction settings aren't dialed in, and it's genuinely hygroscopic — it pulls moisture out of the air faster than people expect, which is a big part of why I wrote a whole separate post on drying filament a few weeks back. I run Push Plastic's PETG for most of this work; it's consistent spool to spool, which matters more than people realize once you're printing functional parts instead of display pieces.
Good for
Outdoor brackets, garage and shed parts, food-adjacent containers (not food-contact unless specifically rated), parts that need a bit of flex before they snap.
ABS: strength and heat resistance, with a catch
ABS is the material people ask for when they hear "strong plastic" and picture Legos — which, not coincidentally, are made from a cousin of ABS. It holds up to higher temperatures than PLA or PETG, it's more impact resistant, and you can vapor-smooth it with acetone for a glossy finish if you want that. The catch is real: ABS warps if it cools unevenly, and it off-gases styrene fumes while printing, which means you want both an enclosure and ventilation — not just one or the other. This is exactly why I moved most of my ABS and ASA printing onto the Adventurer 5M Pro instead of an open-frame machine; the sealed, filtered chamber keeps the first layer from curling off the bed and keeps the fumes from filling the room. If you're running ABS on an open-frame printer in a bedroom or office, I'd stop and reconsider before you finish the roll. Push Plastic's ABS is a solid, no-surprises spool for this.
Good for
Automotive parts, tool housings, anything that sees a hot car or a sunny garage, parts you plan to sand and paint.
ASA: ABS's outdoor-rated cousin
If ABS is "strong and heat resistant," ASA is "strong, heat resistant, and doesn't go chalky and brittle after a summer outside." The UV resistance is the whole pitch — ABS parts left in direct sun will yellow and weaken over months; ASA holds its color and strength dramatically longer. It prints almost identically to ABS (same enclosure and ventilation requirements apply), which makes it an easy swap once you already have the setup dialed in. I use Push Plastic's ASA for anything that's going to live outside permanently — mailbox parts, irrigation clips, enclosures for outdoor electronics, that kind of thing. It costs a bit more than ABS; for a part you're not going to reprint every season, it's worth it.
Good for
Outdoor brackets and enclosures, mailbox and garden hardware, anything that lives in direct sun long-term.
A quick decision table
| Material | Best for | Needs | Avoid for |
|---|---|---|---|
| PLA / PLA+ | Indoor, detailed, everyday parts | Nothing special | Heat, outdoor, long-term load-bearing |
| PETG | Garage/outdoor-ish, semi-functional parts | Dry storage, tuned retraction | High-heat, UV-exposed long term |
| ABS | Heat resistance, post-processing, strength | Enclosure + ventilation | Open-frame printers, poorly vented rooms |
| ASA | Permanent outdoor parts | Enclosure + ventilation | Budget-sensitive indoor prints (PLA is cheaper and easier) |
What my own setup actually looks like
In practice, I split the work between two machines rather than trying to make one printer do everything. The Bambu Lab A1 with the AMS handles PLA and PETG, especially anything multicolor — swapping between four spools mid-print is where the AMS earns its keep, and PLA/PETG are forgiving enough that I don't babysit the printer. The enclosed Adventurer 5M Pro is where ABS and ASA jobs go, because the filtered chamber does the two things those materials actually need: steady heat and contained fumes. If you only own one printer and it's open-frame, that doesn't mean ABS and ASA are off the table — it means you should budget for an enclosure (even a DIY tent enclosure) before you load that spool, not after your first warped print.
One more thing worth knowing
Every one of these materials fails if it's wet, and PETG, ABS, and ASA all absorb moisture faster than most people expect from a "dry-feeling" spool. If you haven't read it yet, my filament storage and drying routine covers exactly how I keep spools print-ready between uses. And if you end up with failed prints or purge waste in any of these materials, that's exactly what the Felfil setup on my bench is for — grinding and re-extruding scraps back into usable filament instead of binning them.
If you're still deciding what to buy for a specific project, reply to this post or reach out through the site — I'm happy to point you at the right spool rather than let you guess.
