Hey Mark,
For a 2 hour flight probably tho something like a 5 hour plus flight with the packing and lugging luggage, going thru security, waiting and then sitting to fly.. nah.. I don't want to take chances. If possible I'd rather lie down and have fun when I get wherever I'm going. Then again I'm not going anywhere anytime soon that I know! Also I find bouncy bus seats and such still bother me, probably so would some crappy coach plane seats!
Thankfully I don't have to go back and forth to Fla now tho if I do travel any distance anytime soon and want to have a good time.. I'd probably still get the 3 seats. That's "if" I travel. SF or somewhere like that ~ just one will do