Our recent experience with a 2.5 hour connection T3 - T5 was eminently easier than previous LHR terminal changes - using Flight Connections Centre seemed speedier, the bus has increased its frequency and it took perhaps 35 minutes from arrival in T3 from ORD to arriving in the Galleries First lounge in the appropriate wing for our departure to OTP (though flight departure gates are not posted until fairly close to departure, staff can tell you the usual departure wing.)
But... security is more TSA-like (shoes off in all cases, etc. though this seems to vary on some days,) and our USA cabin-OK rollaboards were counter checked because they did not exactly fit the confines of the carry-on baggage template. The bags did arrive at OTP on our flight, but were not marked Priority (we were in Business and are both
oneworld Emerald) or the like, and one of the two bags was amongst the last few delivered to the baggage carousel.
T5 is obviously designed as airport terminal cum upscale shopping centre - but the prices, though they may even be duty free, are certainly far from
profit free. I certainly spotted no bargains here.
Our experiences T5 to T3 Wednesday July 2 were quite similar - it did not take long, thoguh US departure shoe carnival etc. does take a little time, and we were soon in the Flagship Lounge. When we emerged for the walk to the distant gate, a chap drove us there n an electric cart, and told us this would not longer be possible in the near future due to the dividers being installed to separate arriving and departing passengers.
(With a side chuckle to
Dave Noble on the Arrivals Lounge info!
)