Two different brand amp in the same setup 5.1?

Hi,I'm thinging to buy a different brand amp for 2 channel.I own a Rotel 1075 for center and surr.My question is when I will listen multichannel(DD or DTS or DVD audio)how they will work?THey will match each other?Each amp has own sound.How they will sound?
Or it's better to have the same brand in amplification?(2 channel+5channel)?
Any advice will be welcome and tkanks in advance
It may be more important to match the center and L/R than to match the center with the surrounds.

I'm running a B&K tx4430 for the front (L, C, R), and a Parasound HCA1000A for the rears. It's quite nice, and it's nicer than when I was running a 5 channel B&K AV5125; and also nicer than when I was running a Parasound HCA1203a for the fronts with the HCA1000a for the rear. I think the fact that the center speaker, and rears are different than my mains introduces more "nuance" than the fact that I have 2 brands of power.
I used a Levinson 27.5 to power a pair of Thiel CS2.2 front speakers and a Bryston 2B bridged for the Spendor center channel (older model; better than the current models, different design). A PS Audio 2C was used for the surrounds.

It worked very, very well once the outputs were matched with the processor channel adjustments. It worked better than a dedicated Parasound HCA1206 6 channel amp which I replaced all of the other amps with in an attempt to streamline the system. The Parasound is gone.
Which is the pro and cons using 2 different brands of power?