I have 99%+ .com and renewals at GoDaddy (with being in the club) are $8.47 for me. I just checked Name Silo, I see $8.99, and I have over 400 domains and if they were all at Name Silo and I was in their discount club, looks like renewals would be $8.79. Depends on how many domains you have, what other extensions you may be invested in, prices could be better at one place vs. the other, etc. I remember somebody spamming the GoDaddy coupon thread, saying how some other places were cheaper, but when you really drilled down the numbers, it wasn't for me or those with lots of domains, generally. You would have to do the math for your own situation.
Tightening up for that #1 spot, 146-142