Don't know about the timings, but if you're visiting during the transition period (say, 10-11:30 ish), SQ SKL is probably the best. They seem to have more "lunch" type options even during breakfast (salads, noodles, rice dishes, desserts, ice cream, etc.). I haven't stepped foot into the LH lounge in years, but I can't imagine that the food is too different. LH lounges are pretty consistent, and IMHO, their LHR lounge is the weakest of the four *A.