I couldn't tell you if Mark Sherman is up to the task or not, however, his staff is. It is better to see how a company handles a rough patch than it is to see them in action when everything is running smooth. I called Shermans' office (and was hooked up with Kayla) when the accountant I was using at another firm tried to scam me via running up my bill on "unnecessaries".
I believe that this office was having a rough week (shorthanded), but they still handled my account relatively quickly and very professionally. Must be a fearsome group when they are firing on all cylinders. Will definitely use them again.