Sorry for asking and answering myself, also my answer will be highly controversial, so bear with me. Disclaimer upfront: I am not associated with preplounge apart from being an "expert" on the site, and this post only consists of my own views. The reason I am posting this is just that I was asked by so many candidates, so I wanted share my honest views more broadly.
If I were to interview again for a consulting firm, here's what I would do once I secured the first interviews: I would do everything you guys are already doing (see other Qs & As), and then book 10 sessions with preplounge experts. I would probably find 3-5 experts I like, do sessions with them, and then do the remaining ~5 sessions with the ones that were most helpful. Regarding timing, I would do the first 1-3 sessions right at the start before getting into it, and the rest over the course of preparation.
I don't really understand preplounge's pricing from a user point, but given the going expert rate of €299 (US$ ?), total cost would be ~3K. To be honest, I would probably even book 20 sessions, just didn't dare to write it. Quick note if you think money is no issue to me: I was completely broke and indebted after college.
So, why would I do this?
Because the application process is super high stakes. Let's do it case style and say there is a value (1) of getting a job with a firm, and there is a probability (2) of getting the job.
(1) The value of a consulting job
The value you assign to consulting depends on your BATNA (= best alternative to a negotiated agreement). If you already have a job offer in investment banking and just want to try out consulting, the delta is low for you. If your alternative is working for some large corporation which you don't really want anyways, the delta is high. Pick your own number. Here, let's assume to get job at a consulting firm is about €15,000 worth more a year compared to the BATNA. (To me that's super conservative - all of it, the job, the experience, the perks, salary & bonus, the international opportunities, the alumni network, the opportunities after quitting - was worth way more than €15K p.a. for me personally).
Let's say you stay in the job for 3 years. So, a consulting job offer was worth 3 x €15K = €45K more than my BATNA.
(2) The probabilities of getting that offer
The most difficult is to actually be invited to interviews, so if you get one, congrats already - chances are ridiculously low.
Say you're invited to the first interview round. At my firm, it was ~10-15% who passed and made it into round 2. In round 2, you have then ~40% probability to actually get a job offer.
Let's assume you are the average candidate. By the way, math dictates there is a 50% probability you are BELOW average, but same as in driving skills, marriage longevity, sexual performance and entrepreneurial success, everybody is convinced to be better than average.
Anyways, if we take the numbers, your chances to get a job at any given firm is:
10-15% (pass round 1) x 40% (pass round 2) = 4-6%
To be conservative, I'll give you the 6%. Let's say you are invited at 5 firms (I only managed to get 4). Assuming the interviews at different firms are independent (they probably aren't as there is some learning curve, but hey). Then your chance to get a job in consulting are:
Probability to be rejected at 1 firm: 1-0.06 = 0.94
Probability to be rejected at all 5 firms: 0.94^5 = 0.7339
Probability to NOT be rejected at all 5 firms, aka secure at least one job offer: 1-0.7339 = 0.2661 or ~27%
So, here you are, after all you have achieved (most candidates I see have amazing cvs), you still only have a chance on average of ~27% to actually land a job in consulting. (But I forgot, you're not average :) )
Now the biggest assumption, I believe that doing 10 expert sessions probably increases your chance to get a job in consulting by 15 percentage points in addition to all the other preparation stuff you're doing anyways. That means if you were average, you get to 42% (from 27%); if you only had a 10% chance prior to the sessions you reach 25%; if you had 50% before, the sessions would get you up to 65% chance of success. Based on all of my experience with >200 interviews this is not unreasonable at all, it's probably higher actually.
So, now to combine (1) and (2). Your expected additional value from doing the sessions is:
15% (performance increase) x €15K x 3 years (delta consulting value to BATNA) = €6.75K
So by taking the lessons, you probabilistically make €6.75K, while the cost is only €3K. That's a steal.
To do a sanity check, let's say you fail all interviews. How much would it be worth to you to just retake the interviews? To me, that would probably be at least €10K. Or, how much would you be willing to pay to get an offer outright after failing all interviews? To me, that would probably be worth north of €50K knowing what I know now and given that consulting opened up so many opportunities. Finally, even if you fail after all, think of the case study prep time as a mini-MBA. It's actually really useful no matter what you continue doing in life.
Chances are you disagree or accuse me of having hidden motivation to do more sessions or something.
- First of all - this is what I have told many people in private, so it's just fair to share with a broader audience, and I know candidates doing this already who you are competing with. More information is almost always better.
- My preplounge activity is completely immaterial to my finances. Frankly, it's actually just an expensive hobby given that I could spend more time on my own business. This post took me close to 1h to write which I did for free, same goes for the other forum activity. And even the money I make from sessions (after preplounge's share, VAT, and other taxes) just covers a few extra dinners out with my wife each month, so the main reason I'm spending time here is because I like doing it.
That's it - make of the post what you want, and no matter how you personally prepare, I wish you all the best and success for your interviews! :)
p.s.: I actually failed my first interviews miserably because I wasn't prepared enough. Also, main feedback was that I came across as nervous and insecure - so I ended up going to three coaches/psychiatrists, and doing an additional three sessions with the one that helped me most. Best money I have ever spent in my entire life.