That's not a good comparison, because Carter, Reagan, and Bush I likewise replaced all US Attorneys in the first year of the first term. That "move" is not controversial.
Replacement other than attrition at the start of a second term, as the GWB administration did in 2005, is controversial. We still don't know how far down the chain of command the power to fire a US Attorney goes. President Bush said he was NOT involved in the firing decision, and we don't know who exactly made the firing decision.
That said, the Walpin firing merits plenty of attention. It is unusual, and the reasons given, so far, don't hold water.
But then why did the MSM get all over Bush for firing just 8 in his second term and no mention of Clinton?
On the other hand, firing the IG without notice OR cause is against the law. BO's own law. Whether or not it is constitutional is immaterial, because BO certainly believed it was constitutional, or he wouldn't have sponsored it....Righhhhht! 'Nuf said.