Personally a combo is great. On the routing: EDI-LHR-BOS, you get a quiet airport (EDI), before travelling to the busy ones (LHR and BOS). This makes it interesting. I had to show up at EDI early because I was travelling with friends, and their flight to BRU left two hours before my BA flight to London. So after milling about the check-in area, I checked-in, went through security and sat and watched the traffic of EDI. It was very nice. I had my headphones on, and I was able to sit quietly, read a book, with no hassle. Compare that to 90 minutes later, deplaning at LHR. Walking to a bus, being shuttled across the airport, then after a long walk through T4 to my gate, having to be queued up for 20 min, while the understaffed departure was handled. There really is no comparison. For travelling I much prefer a quiet airport, for spotting the busier, the better.
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