I have not used them, but many Brethren have.
Feed back seems very positive.
Here is one of many threads here:
"Flirtin' with Disaster" BBQ Team (RETIRED)
FBA and KCBS Cook and Judge.
Former owner of a WSM, a Smokey Joe, a Charbroil Commercial gasser (junk), the legendary "StudeDera", a FEC100, a Fast Eddy PG500, and Sherman the Wonder Trailer.
Now cooking with a Yoder YS640
Proud Pellet guy cooking on real wood.