I have both a Brinsea Octagon 40 and an RCom 20. I prefer the RCom only because the humidity is easier to maintain rock steady. Both keep the temp rock steady. I put them in a room that doesn't have significant temp fluctuations and I don't have any problems.
I pour in water to the Octagon 40 using a small watering can. I have never had any problems even if a couple of the eggs in the vicinity of pouring get a little water on them. They dry off soon enough in the warmth and no hatching issues have occurred.
The dividers I set such that the egg doesn't go rolling across the tray when the unit tips, but I don't set them so tight that the egg might be compromised. If there is 1/8 to 1/4 of an inch space on either side of the egg and the divider, the egg will just move slightly and it won't be damaged. I have hatched a lot of eggs in there. Sometimes, if I have a lot of eggs, I take the dividers out entirely and set the eggs against one another and when they tray is full, they all just stay in place with no need for dividers. Also I can fit more than 40 eggs that way!
I use the R-Com 20 as my primary hatching incubator because I think it's easier for the chicks to move around in it than in the Octagon 40.
I love both of these bators and have had no trouble with either, and would recommend either to anybody who wanted a good quality bator that gives good hatching results.
I pour in water to the Octagon 40 using a small watering can. I have never had any problems even if a couple of the eggs in the vicinity of pouring get a little water on them. They dry off soon enough in the warmth and no hatching issues have occurred.
The dividers I set such that the egg doesn't go rolling across the tray when the unit tips, but I don't set them so tight that the egg might be compromised. If there is 1/8 to 1/4 of an inch space on either side of the egg and the divider, the egg will just move slightly and it won't be damaged. I have hatched a lot of eggs in there. Sometimes, if I have a lot of eggs, I take the dividers out entirely and set the eggs against one another and when they tray is full, they all just stay in place with no need for dividers. Also I can fit more than 40 eggs that way!

I use the R-Com 20 as my primary hatching incubator because I think it's easier for the chicks to move around in it than in the Octagon 40.
I love both of these bators and have had no trouble with either, and would recommend either to anybody who wanted a good quality bator that gives good hatching results.