Actually, water bottles are made out of PETG, not PLA.
PETG doesn't smell at all when you print it. I've just made hundreds of COVID-19 face shields out of it.
ABS is what outgasses, although I inadvertently printed some and it didn't smell as bad as the adhesive on the PEI sheet on the Monoprice MP10 did. Actually, it didn't smell at all, but it does have that reputation.
I'm the John in the thread.
Greybeard, those look like some nice printer upgrades! My HICTOP was a CR-10 clone, oddly we seem to have different base printers. I eventually did convert mine to a "prusa" clone, called the CREARIBO. That was a rewarding upgrade, but not easy.
So, I did get the dual extruder working more or less with the holder that was mentioned earlier in the thread, but even with it's great way to adjust the nozzle height, it was a colossal PITA. The two nozzles have to be very precisely tuned as far as separation and I also had to compile firmware to do that. I'm now pretty good with Marlin firmware, but it was a long road. I also burned out my original Melzi board by inadvertently unplugging a stepper while power was to it, so I had to upgrade boards. I eventually used a BIGTREETECH SKR PRO which is a great board, but required a then-development branch of Marlin to properly use the SD card to store settings. Was a long road!
The V6 extruder is fine - lots of compatible blocks and all.
== John ==