I would personally take the 250kw traction motor rating stated in the Today's Railways article with a pinch of salt. No other articles have highlighted / quoted the traction motor rating, and as other posters have pointed out it is just too low an overall rating for 125mph train. It's also the same rating as the 385s traction motors, so maybe some copy and paste assumptions. The Today's Railways article also states the wrong number of toilets when comparing the 810s to the other 80Xs, stating that the 5 car 80Xs only have 3 toilets when they actually have 5 (2 universal and 3 space savers).
The March issue of Modern Railways also has an article on the 810s, which mentions two new facts not mentioned in previous articles. Firstly that the two space saver toilets in the centre TS will be located at either end of the coach instead of opposite each other as on the 80Xs. The second is that the TFT PIS screens won't just be on the bulkhead ends of the passenger compartment but also in the vestibules.
In addition to this article is a side article regarding the seating on the 810s by Ian Walmsley. It mentions that seat pitch will be 800mm, which is am amount Ian Walmsley approves of, but to allow this it does mean there are only 6 bays of 4 seats, down from 8 bays which were originally planned and as found on the other 80Xs. As mentioned the seats will be FISA Leans, but apparently will have a more reclined position than their GA counterparts, of 107 degrees to horizontal for the EMR seats vs 102 degrees as found on the GA seats. All sounding positive, but the true comfort test will be sitting on these in reality.