What size WSM?
Vent positions top and bottom?
What fuel?
We neeeed ALL the details to properly diagnose the situation.
I can get 350 on my 18.5 wsm using the 4cfm fan..takes a bit of time but it gets there no problem for HH brisket.
I've got one and have no complaints thus far. Prior to owing the WiFi unit i used the DigiQ 2 DX. Both work as advertised. There are less expensive and more expensive options out there just depends on the bells and whistles you are looking for.