[Financial modeling courses] is "breaking into wall street" or "wall street prep" better?

I can't speak for Breaking Into Wall Street's (BIWS) modelling package, but Wall Street Prep's modelling packages are a good offer. They give you a thorough breakdown of:

1. The different valuation methods (DCF, comps, precedent transactions, LBO, etc.)

2. How to construct a model for each valuation method

3. The key mechanics of each valuation method (e.g. what are the inputs that will have the biggest influence on a DCF valuation?)

See: https://www.wallstreetprep.com/self-study-progr...

If you look at Wall Street Oasis (well-known investment banking/finance forum), Breaking Into Wall Street's "Interview Guide" is very well known and well-reviewed by users.

See reviews: https://www.wallstreetoasis.com/forums/biws-and...

See the guide: https://breakingintowallstreet.com/biws/investm...

Are you preparing yourself for corporate finance or investment banking jobs/interviews? Then you'll definitely want to familiarise yourself with what a typical M&A process looks like. Here's a good guide to the 8 essential steps of the M&A process.​​​

Both are. There are handful of other service providers around.

Avoid the decision making paralysis.

If you need it now, just buy.

Else, wait for seasonal promotions .