I was at Arpege a few weeks ago for lunch and had their vegetarian menu which was French-Asian fusion. I fact I thought it was tilted more Asian than French. The dishes can be hit-or-miss depending on your taste. They started with a vegetarian herbal soup that tasted like they used the herbs from "Bak Kut Teh". But it didn't taste right to be me because I am used to the soup cooked in pork. OTOH my favorite dish was a melt in your mouth vegetarian sushi - it was so good.
I thought their table knife was a good design and a nice touch. The amount of food served was just right.
I also went to Taillevent for lunch initially intending to get the regular lunch menu. When I got there their 8 course tasting menu looked more appealing and I was assured that the portions were "small". I was satiated by the 3rd course. For the 5th course they served me the biggest piece of foie gras I have ever seen in real life. Then the meat course arrived.
If I return to Taillevent, I will have to remember to pace myself and only eat a portion of each dish. Interestingly, at Arpege I was served a number of additional dishes not listed on the menu while at Taillevent most (if not all) of the dishes served were listed on the menu. Arpege was more casual than Taillevent. At Arpege I was one of the few dressed in coat and tie whereas at Taillevent most men wore at least a coat. I thought there were also more tourist looking people (like me) at Taillevent.London
I was there over a year ago. I tried to get reservations at Fat Duck but failed. I went to River Cafe but was underwhelmed. In London I enjoyed relatively simple food much more (e.g. soft boiled eggs, fish & chips, India food). Sheekey's fish pie was quite good too.