3 year old male Jack Russell 2nd dog for companionship

Question
I read a question about a 3-Year old Jack Russel and what type of dog would be good as a companion for him.  The answer suggested a female rescue dog, which is what I would consider anyway.  My question is: Should the new dog be another JRT?  Or would a beagle be okay.  I saw in our newspaper a 3-year old JRT/Beagle mix and wondered if that is a sign that those two breeds are compatible.

Answer
JRT/Beagle mixes are a common mix now and have seen and met a few,all seemed friendly,so I think this cross would get along fine with your JRT

isn't as a much the breed,as the personality,so it might be good to have them meet somewere that is netural,and have them sniff ect