Choosing between internship offers: BB Trading or ER at large LO AM?

Hi guys. I'm a UK Humanities student who got lucky during spring week applications and emerged with a few decent springs. I managed to convert two of these and have ended up with two very different conflicting internship offers. I'm kind of at my wit's end about which one I should choose and I really don't want to fumble. Please knock some sense into me.

BB Trading: this is at a BB that's very good for markets (JPM / GS) in London. The intern cohort will be much bigger and I'll definitely have lower chance of grad scheme conversion with how cutthroat getting ROs can be. I don't know what desk I'd be on and would have little input, although I did position myself as someone more interested in distressed credit so that might have some bearing. I don't have a massive maths background, I've never done trading before outside of a few sims, and I have no idea if I'd be good at it or terrible; the interviewers liked me but that's literally the only proof I have that I'd be non-awful. Having said that, it's a Big Bank and rejecting that name feels genuinely insane. I don't think I'll ever get another shot at trading with my humanities background, especially somewhere so well-known for it.

ER at very big (500bn+) LO AM, also London. Kind of the opposite story. I've already completed a mini-internship of sorts with the firm as a follow-up from the spring week so I know people from both the hiring and the research teams quite well. I know I'm decent at the role because I performed well in the mini-internship and was explicitly prioritised r.e. the summer. I'd be part of a much smaller cohort and would stand a very strong chance at converting. The firm itself has a great upwards pipeline into PM roles.

Both have similar comps (trading a little higher but the internship is shorter by a week and sign-on bonus is lower so it evens out). 

I know I'd like ER, and I like the firm too. I don't know if I'd like trading. But I don't know if I'll ever get this chance to try it again, and the Big Bank is That Big Bank and I feel like a madman to turn them down. Maybe I'm just getting horribly prestige-dazzled? 

I appreciate this is a bit of a lobster-buttery situation but the two are so different and I really, really don't want to fuck this up. Any advice as to what the better choice is would be so appreciated--I feel like I'm fumbling in the dark at the moment.