Boutique Pre University Internship - should I go for it?

Hello everyone,I'm from the Scandinavian region and have recently graduated from high school. Currently, I am on a work experience programme at a Big Four Corporate Finance-division for three weeks in London. This fall I will start my undergraduate studies at one of the target schools in the UK. During the final months of summer I have an opportunity to do a 2-week gig at an EB's regional office (Scandinavia). Do you think it will leverage my application for Spring Weeks enough to do it. Obviously it will be a nice merit to have on my resume, but this means I wouldn't have as much time to prepare my cover letters and everything else that comes with it. What do you guys think? They have a pretty strong position in the Nordic market, advising on a couple of a $Bn deals (which aren't common here) and good deal flow. Is it just to good of an opportunity to miss out on?

Alright, thanks everyone!Its just that I've heard that the cover letter takes up a significant amount of time, especially when English isn't your mother tongue. Anyways, I made the same conclusion as all of you.

Cheers