I've tried it
I've tried it, and the news is not good.
Prices have gone up a little, food has gone down a lot.
Prices have gone from a minimum of £169 to a minimum of £179. That's not great news.
The worse is the food. I used to travel in Leasure Select for my personal travel because it provided a good warm meal with much better seating (compared with economy). The odd £40 more or so you add to pay for this service were well worth it.
In the new class, you still get the nice seats, but the food has become sparse, and, frankly, terrible. You are served three tiny dishes (in my case a bit of saucisson, a tiny, tiny sandwich, and a bit of carrots). Together, they may replace a normal starter, but will never replace a full meal. In addition, the food is very disappointing. You can buy a much tastier and plentiful meal at the train's bar for less than £10.
So it no longer makes sense to use this intermediate class as opposed to economy. I don't really care about the improved seating as I can survive a couple of hours in the "ok" seat provided in economy, but I do care a lot about the food.
From now on, I'll book in economy, deal with the okay seat, buy myself a nice meal, and save the difference.