I've never taken IELTS, but from what I've heard, it's easier to get IELTS 6.0-6.5 than TOEFL 100, but it's easier to get TOEFL 105 than IELTS 7.0-7.5.
Regardless, the same strategies can be used on both speaking sections. Here's what a former student wrote to me a few days ago:
Since my TOEFL score didn’t improve so much, I finally switched to IELTS in May. And I got 7.5 (Listening: 7.5, Reading: 7.0, Writing: 7.0, Speaking: 8.0). Additionally, I got 8.5 for speaking on the next IELTS. Although speaking for TOEFL is a little different from the one for IELTS, I used a lot of the strategies which I learned at E4TG for IELTS. That’s why my speaking score was higher than other sections, which is really rare for Japanese students.Please use English well!