Sometimes Plum Tree is as good as anything one can get anywhere in the country, when it comes to American Chinese food. Other times it can be quite bland. Not sure if it's a change in chef factor, or simply how busy the kitchen is...but when they're on, they're ON.
No buffet, this is a sit-down/take-out Chinese restaurant. The staff are always very friendly and engaging, but often are in the position of having to do too many things at once, which slows down service.
Takeout is a breeze and generally very good. Just double check to make sure you got everything you ordered. Again, it can be hectic in there and the staff can just do so much. Hopefully they can afford in the future to hire another person to take the load off the existing staff.
The inside really needs to be updated. It doesn't look like it's been painted or refurnished since it opened. I know restaurants these days operate on a very low margin, so investing in infrastructure can be prohibitively expensive but sometimes as a business owner you have to bite the bullet and just do it.
If they could get the quality consistent, streamline the workflow and spruce up the inside, they could be the premiere Asian restaurant in the Tri-Cities. Some signage and advertising probably wouldn't hurt either. :-)
(The Tai Chien Chicken (their version of "General Tso's") is nearly always perfect. Not excessively spicy, and the chicken is lightly breaded in a very light sauce. Highly recommended!)