Hey jandsferguson!!! I DID NOT KNOW ONE THING about hatching upright until I came across a post here on BYC about it, SO...I typed in upright hatch (ing) in the search box and I read as many post as I could for weeks and weeks. My first 2 batches I hatched traditional on their sides...my 3rd I figured Id gibe upright a try and I LOVED IT. I was really scared at first because you will find in the post some folks who love it and had great success others did not have such good luck. I decided to take the chance and it was a more than perfect hatch BUT I was willing to take the chance with a batch of eggs that I was afraid I had run too hot anyway. Luck was on my side this time and it was AWESOME. I am going to do it again and see what happens. Baby nipple holders sound perfect...I was short a few egg carton cells so I cut rings off a tiolet paper tube for 4 of my eggs...all was fine, the tube rings worked just as well. Im sure those nipple holders will be perfect. When that first chick starts to zip the shell...just walk away my friend & go have a coffee or tea and let the lil birdie do its thing, thats what I had to do lol. I had a 100% hatch this 3rd time. As far as the temperature, well I cant wait to see what has happened with my birds. The first two were several degrees cooler than my 3rd...if my first two have mostly hens and the 3rd mostly roosters then I just gonna be inclined to believe the temperature does play a factor in the debelopment of the sex of the chicks...kinda like in reptiles. I have rread both ways on that subject too lol! Good luck buddy and keep me posted on your hatch!!!