Hopefully yours is flatter than my Trend sub-base, which is unusable. It's cheap plastic with sink marks all over it. I now use one of the Axminster aluminium ones, with a low-friction coating on it.
I must be unlucky, but everything of Trend's I've ever bought has been a disappointment. The worst was their T Square:
http://www.trend-uk.com/en/UK/product/RTS_1000/3/194/router_t_square_1000mm_.html
I was looking forward to a nice large accurate square, but it came in two pieces with the instruction to screw them together square!
I've had a number of their cutters too, and I would put them in the bottom class for quality. What I don't understand is why people think their stuff is acceptable.
Andrew