Geeetech

Hey all! So I recently purchased a Geeetech A20M (dual extruder) printer. I've never owned a 3D printer before but I do have a couple friends who have them, and as such I've seen some of the build processes and issues with a few different models. So I'm still a complete noob with these, but I'm not scared to get my hands dirty. I'm looking at purchasing the Auto Level Sensor for it and was wondering if anyone has any experience or thoughts regarding this add-on. I'm also wondering if anyone could point me toward some trusted brands/stores for filament, or tell me what is good to keep an eye out for and what is good to avoid as far as the filament goes. As of right now I'm only looking to print mono color plastics (not sure if it's actually called plastics or if it goes by another name.) If this printer allows it (or if I can mod it later) I'd eventually like to toy around with some of the metal stuff, but that is not a priority at all right now.

Thanks in advance!
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