I really enjoyed that episode! Hearing the premise I was sure it was the product of the showrunners brainstorming ways to cause maximum possible humiliation for the candidates, but business decisions aside both tours looked fab. It was great to see more of Megan after she initially seemed so quiet - honestly don't think I even registered she was on the show until about episode 3 - and I thought she defended herself really well in the boardroom. She and Simba obviously managed to turn things around with the older ladies who thought they were getting a sedate historical tour, and the guests must genuinely have loved it if no-one asked for a refund after their food was an hour late.
On the other team it was nice to see Marnie getting to be silly and have some fun after the obvious friction between her and the others in previous tasks, and again it was clear the guests were having a great time. Even more impressive that they pulled it all off after one day's prep when none of them are professional performers. And then to cap it all the right candidate got fired, instead of someone decent getting shafted for spurious production reasons! (Bizarre that Mark decided to PM this of all tasks, when he's so obviously not a people person - maybe he just wanted to be really sure he wouldn't be put on the acting team 
)
In recent years it's felt like they've intentionally picked all the worst candidates and then set them up to fail in every task, and while that is admittedly where most of the entertainment comes from, I think they sometimes forget that for the show to be enjoyable we need some good characters who we're rooting for too. Watching an interchangeable group of irritating dumb people be incompetent week after week is boring - most of the time I feel like I'm watching out of some weird Stockholm syndrome rather than because I actually like the show. I'd love to see more episodes like this that are actually fun instead of vaguely depressing.
(As an aside it really annoys me how they can't win in these tasks - if they pick the expensive options and lose they get patronised about how 'this is a PROFIT task, why wouldn't your priority be keeping the costs down?', and if they pick the cheap options and lose they get an earful about how 'the guests are paying £xxx for this experience and you gave them half a sausage served on a squashed potato, there's no point keeping costs down if it means people are going to ask for refunds'. I was glad Megan pushed back on that because picking the budget food option when she thought they were selling tickets for £180 would have been ridiculous.)