Best Insurance Companies for large Schedule Policies?

I am an Insurance Agent who works in the Real estate Space with Investors, working with large Property Schedule policies. 

I am curious who you as an investor know is a Good insurance Carrier, who you use, and who you Avoid, and who you have heard scary Stories about? 

I will tell you personally working in Michigan - I love to work with Fremont Insurance, they are able to do many 1-4 Unit Buildings on one property Schedule...A lot, and its a really good policy, and the billing is pretty easy, so I love working with them...And they are always very good with Claims. The Coolest part is when my Client gets a new Buy and Hold, I can simply just Add it to the Existing policy - rather than going through writing him a new one, So he just tells me the Address and I just add it to the policy. 

Just curious to hear Investors thoughts on who is good to use with Insurance, and who is not. 

Thanks!