I've owned an STI before and have to agree that it's ridiculous to compare one with an M5.They definitely should not have used the word "imitator". I think the GT-R is a less expensive alternative to the LFA.
The writer of the article clearly knows very little about cars, but what do you expect from Popular Science? They are almost as credible as Consumer Reports. I also laughed when he compares a WRX STi to an M5. That is a joke.