I'm in the design process for an indoor (Duh!) studio using fluorescent lighting. I'm going to be using my A1 and HV20 together and mixing in post.

At this point I can go with any color theme I want, so I want it to be HV20/A1 friendly--in the sense the two cameras see those colors pretty evenly.

I've seen on other threads that reds are the WORST? True? Yellow I heard is hard too. How are greens and blues? It's for a kids' program so some bright colors are needed.

More specifically to my post, I don't to have to do ANY color correction in post if it can be avoided.

Just shoot in black and white and you'll be good.

Sorry, couldn't resist that:). Primary colors in the digital world are not so difficult as they were in analog, but deep reds want more light. If you white balance correctly you shouldn't have to do any color correction. But if, for example, you have a light skinned person close to a green wall and get a bounce onto the face, you might need to take out a little green.

So are you saying that even deep red in a shot will look the same in the HV20 and A1 with proper lighting and WB?

I'm setting up my studio now and have the choice to go with blue or red as the overall theme color. I'll be using the HV20 and A1 together. I will have this set light up right, so if I do, am I okay with reds?

no the colors won't be the same, that has already been proven. Someone needs to do extensive testing to figure this out. I and several others are in the same boat.

If it helps, I went thru a similar process moving from and XL1s to an A1. I wanted the A1 to look the same. Here's what I did using a studio setup:
Get the camera to look like you want (in my case the XL1s)
Note the exposure and custom preset settings
Use the camera to take a photo
Put the next camera on the tripod
Adjust exposure so you have a good setting
Take a photo
Tweak the custom presets to make it look like the memory of the first one
Take a photo
COmpare the photos to the original photo and adjust custom presets until it matches. You can see the before and after compared to the XL1s in this thread:
http://www.dvinfo.net/conf/showthread.php?t=114952

So, try the settings I used and then make the HV-20 look like it?