Which is the better (2nd) entry level 3d printer? Dual Ext Delta vs Metal Frame i3 ?

[rhd]

I've caught the 3D printing bug. An M3D that I ordered in November arrived a week ago, and while I'm having a lot of fun with it, three limitations have already begun to stick out like a sore thumb, namely:

1. Small build size. 100 x 100 x 90 cm is all I can reliably print.
2. Lack of heated bed. I mistook the fact that they claimed it could print ABS for an indication that it had a heated bed. It doesn't.
3. Inconsistent printing / lots of failures.

I'm not unhappy with the above, and I'll probably keep it, but I want to grab something a little bit better. I've narrowed it down to three options (all are from 3dprintersonlinestore, but I don't have any particular affinity for them / connection with them / any reason to think they're any good - they just happen to ship worldwide for free, which is important since I'm in Canada):

Professional Fully Assembled Wanhao Duplicator i3 - $405
https://www.3dprintersonlinestore.co...rusa-i3-wanhao

Geeetech Dual Extruder Delta 3D Printer Kit - $405 single / $447 dual extruder
https://www.3dprintersonlinestore.co...3d-printer-kit

He 3D Dual Extruder Prusa i3 Kit - $425 dual extruder
https://www.3dprintersonlinestore.co...ruder-prusa-i3

Does anyone have any thoughts on these three printers (vs each other, or even vs something else)? If my budget is in the $400 to $450 range, is there a better solution? I know there are a lot of better printers out there for a larger investment.

These both have heated beds, and the Geeetech can be purchased with dual extruders (which I'm on the fence as to whether I'd use). I'd love any feedback anyone has, even if it's to say "don't waste your money" etc. That said, I'm hopeful that there is an option that can get me a heated bed, larger build size, and print quality comparable to the M3D, with a bit more reliability, for under the $450 (or $500 max) mark, shipped.

Thanks in advance for humouring the kind of question you must get a million times a day from brand new users