Flight connection

Hi all
Doing the ex Dub thing for first time to LA in October. We only have 3 hours at Heathrow so was wondering if it is quicker to use flight connection transit or leave terminal 2 and walk over to terminal 3 and check in again. Trying to make most time available in CH of course. Thanks

Can often come down to time of day but the time to walk landside from T2 to T3 is minimal and if you have use of the UC security then I would go with landside.