I was lucky enough when I bought my Ender 3 to get a Creality branded glass bed thrown in with the deal. Actually I think that this was really a sweetener due to the fact my Ender 3 has the old 8 bit processor running Marlin 1.1.x software not the new all singing and dancing Marlin 2.x supporting 32 bit processor.
Frankly though, I’ve not missed the 32 bit software upgrade (though that may be because I don’t have it!) For what I use the printer for, it has never been an issue being limited to Marlin 1.1.x. I don’t expect many other people would find it that limiting either. But obviously some would. You can though easily upgrade to 32 bit if you so wish. Here’s one advertised on Amazon here with several hundred 5 star ratings.
But I would not want to go without my Ender 3 Glass bed. While I’ve used the resin bed that also came with the purchase (mainly to see what it was like), I’ve found the glass bed much easier to use and particularly to clean! (here’s one for less than $20 on Amazon)
The Ender 3 glass bed is for obvious reasons much heavier and thicker than the resin bed, but even when poorly/weakly secured I have never (yet) had it move on me. Neither have I ever had a problem with bed heating.
My glass bed gets a bit of a hard life. I’ve used all sorts of different adhesives to ensure the first print layer sticks. I’ve used Pritt Stick (standard school glue – here on Amazon if you want) , Spray Mount (re-position-able Adhesive spray – also here on Amazon) to Hair Spray (I’ll leave you to find that one!). They all seem to work OK.
Currently I’m using (on the Glass bed at least) re-positional Spray mount. It’s quick clean and effective and it gives a really good adhesion. Maybe though it is a little too good in fact. It it tends to bake on. But after printing I’ve always been able to knock the print off the glass bed. It takes some elbow grease to clean it off the glass but I’ve found that it does come off eventually. But I wouldn’t use it on the resin bed (again anyway!). You can see below that the adhesion is perhaps a little too good and it has been a devil to clean the resin bed without damaging it.
I’ve found that cleaning the glass bed especially when used with Pritt stick is a doddle. I take it off the Ender 3 and then using soap and water, or even cream cleaner. It comes up like new. Even using a mildly abrasive scouring pad has not damaged it. Whereas my attempts to clean the resin bed (as you can see) has been less successful. I don’t think I’ll try and get the remains off this resin bed. As I appear to be now damaging it. I definitely won’t be using spray mount as the first layer adhesive on the resin bed again either!
I’ve secured the glass bed to the build plate using the standard spring clips. Two appear to be fine. I’ve also used cut-down book bindings (see this post) . I’ve also simply taped it down with sellotape. All have worked. But the sellotape went a bit gooey due to the heated bed.
If you don’t have one, I’d recommend you get a glass bed. If though you are looking for a self leveling system be warned the CR Touch is incompatibe with the 8 bit Ender 3’s. More in this post.