Well, hard to say. It sounds like artist #1 could be trying to be constructive. In all honesty, just because several people use the same character it doesn't mean they will all get the same results from it.
If artist #1 is usually complimentary, it's hard to believe they'd be deliberately mean.
It's hard enough to leave constructive criticism, I remember one image I looked at that had a lot of the usual back-patting but what I saw was a pixalated texture that could have been improved upon. No one else would say it and the person thanked me for the comment and asked for suggestions.

If your friend want's constructive comments consider posting the link and asking for opinions.

...... Kendra