I'm something of a beginner in Aikido myself (4 1/2 months and counting!) and I disagree whole-heartedly with you..
I've found working with people who started at around the same time as me, or who've been practicing not a lot longer, to be a great way of seeing what I'm doing wrong..!!
Not to say that the people are doing things sloppily or anything, but that if I see them doing something wrong I normally find out that I'm also doing the same thing wrongly, and so I find it invaluable from a self-analysis point of view to work with others of around my level of experience. Obviously it's nice to work with one of the more experienced Aikidoka at my dojo, who can pick out problems for me, but I can't expect them to do all the work for me..!
Just a thought..