The high frequency rates of televisions that were launched around the same time as this TV range from 50Hz to 1,600Hz. With a high frequency rate of only 50 hertz, the 42LB5610 has a quite slow high frequency rate compared to most of the other TVs of this spec and age.
There are a number of other 50Hz refresh rate TVs currently available that you might want to consider including cheaper TVs such as the LG 42LB550 (£299).
If this TV high frequency rate is too slow for you then you might want to look at the Hisense LTDN40K370 (100Hz and higher rated); or the Cello C40227 (60Hz and cheaper), or the Philips 40PFH4100 (£269.99) (60Hz and cheaper).
What does "high frequency rate" mean?