Extruder for a first time user?

Hello once more Hope I'm not bothering you too much by creating a third topic in a few days...

This time I need help in choosing a coldend + hotend combo for bowden type of extrusion.

During my research I've found that people generally stay away from Chinese counterfeit hotends, both to get a better quality product and to support the original creators. And I'm seriously planning to get an original product, since I am already getting linear guides for my printer and it doesn't make much sense to get them unless every other part in the build can keep up in terms of quality... BUT there's one catch - I've never dealt with 3D printing before, and I'm a bit nervous of wrecking my expensive hotend. Reading about those chinese clones, a few guys mentioned they somehow destroyed their hotends but it wasn't a big deal "since they're so cheap". Here's what I'm asking - How can a hotend be "destroyed"? Can the originals be fixed more easily? Should I just buy a cheap one to experiment with?

As for the coldend, I would prefer to use my own Nema23 motor (of which I have surplus), and just buy (or make) the hobbed bolt part. Looking at some more popular designs it doesn't seem too complicated to replicate them having access to a 3D printer... without one - a bit harder.
Here's what I'm asking - does making a shitty one in order to be able to print a better one and just stay with that seems like a good idea? Or should I just buy a "proper" one and be done with it? Are you a fan of geared solutions? What kind of a coldend design would you recommend?

By the way, I'm making a CoreXY type of system, which *should* be capable of high speeds. What design choices could be made to increase printing speed? A powerful coldend plus a hotend capable of melting the material faster? Honestly, I have no idea and would like to get a solution with a best price/performance ratio...

I've gotten about 5 metal cheap Chinese hotends from 3 different vendors between $8-$15. They all look the same on the outside, but the machining is different between the vendors with the cheapest being the best (oy). For a couple I had to print a filament guide that is threaded in below the push to fit fitting because there was too much space and no cone machined on the bottom to guide the filament. The filament would curl up inside the hotend instead of being guided into the nozzle. I only use the ptfe lined hotends since I only print PLA and ABS, and they all print well.

That said, since E3D brought out the E3DLite, and it's in my budget range. I will probably buy one of those next time I need one.

With a Nema23, you probably don't need gearing for your extruder. If you could find a hobbed pulley to fit its shaft direct drive should be fine.

Quote
madmike8
With a Nema23, you probably don't need gearing for your extruder. If you could find a hobbed pulley to fit its shaft direct drive should be fine.

yeah, IF I could find a pulley like that. It seems like the common bore sizes on those are 5 and 8mm, so that won't work...
Besides, even though my motor is Nema23, it's a low torque one (5200g/cm ~72oz/in) pretty much like all the regular Nema17s... just makes mounting it non standart...

anyway, I think I'll go with some 00str00der variation for my cold end. Then I could pinpoint the needed torque/speed setting by changing the gear ratio on it.

Might as well try my luck with a Chinese hotend, but I'm waiting for more opinions on that.