I love my Ender. If you (OP) have never done any 3D printing before, do yourself a favor and learn to print with PLA. Get your skills honed in until you can reliably print with that, then worry about moving to PETG. PETG might not be harder to print, but it exaggerates the problems that you learn to overcome with PLA. PLA is stringy, PETG is worse. If you're pulling your hair out trying to get PLA to stick, PETG is going to make you throw the printer through a wall.
On top of all that, there are countless resources for help learning to print, but they're typically geared towards learning to print with PLA. If you're looking for help learning to print with PETG, a lot of those resources will make the assumption that you have PLA experience meaning instead of teaching you the basics, they're teaching you how PETG is different.
If getting a printer and some PLA is like learning to drive, getting a printer and PETG is like learning to drive a bus. You can do it, but it's easier to start with one then move to the other.
I printed a media basket in PLA (2mm walls) and within 2 months it was so brittle I couldn't move it to change media anymore. Just my experience.
I've had a PLA frag rack in my tank for years with no problems. It gets bumped into, taken out and scrubbed, the suction cups break loose and it falls. It feels as strong as the day I printed it.
Also, something worth noting about the Ender 3 (and probably most commercially available hobby grade printers), it will work out of the box. I've seen many, many times where people buy it, upgrade the board, the firmware, the hot end, adding a BL Touch, covering the build plate with tape or glue or hairspray etc, and it still won't print correctly. My first question to them is if they ever had a successful print (particularly before all the upgrades). Assuming they haven't, it's a lot harder to figure out the problem. Is it simply an environmental problem (ceiling fan blowing on it, too close to an AC vent?), is it a slicer issue? A firmware issue? The BL Touch isn't calibrated? Who knows? But if you make sure you can print, and print reliably, before you start changing things, it's a whole lot easier to troubleshoot.
The only thing I don't have a problem with people swapping out ahead of time is the build plate. IMHO, the Creality glass plate is considerably easier than the factory magnetic one, but that's me. And, with that, remember, it will work out of the box. Don't go slathering all kinds of stuff on the plate if you can avoid it. If stuff doesn't stick, clean it and then clean it again and keep cleaning it until it sticks. If rubbing alcohol doesn't work, try taking it off and cleaning it with warm water and soap. And don't forget, there's no rule about printing in the middle. If it's not sticking well, try printing it off to the side.
And then when it finally prints, you really don't need to go to town trying to chisel this thing off the plate. PLA, especially on a glass plate, will, if you let it fully cool, release from the build plate with no more effort than picking it up from a table.
Anyways....off to thingiverse to find something fun to print today.
