Is it alright to mix-and-match brands for these? I know it's kind of a stupid question, but I just want to be REALLY FREAKING SURE!

 

i am using 2 different upper control arms on my 4th gen and there are 100% identical in dimesions and the ball joints seem identical too so i dont think its a problem. 1 is from checker (149.99) and one is from autozone (90.99)

 

To save everyone from another thread being created for a related question, should I go ahead and replace all of them (front and back) while I'm at it? The back ones don't look TOO horrible, but they've been on there a while. The front ones are shot to hell and have been for about the past year.

Here's pics of the front ones:
Left: Right:

Here's the rear ones:
Left: Right:

 

As long as your doing the work I don't see why you wouldn't. I usually do that a lot when it comes to those kinds of parts that way I know where all my suspension sits.

In fact recently I had an axle that shredded its boot so I swapped both axles out...it gives me a feeling of comfort knowing exactly whats up and when they were changed out instead of any guessing.