Sharing what I've read from the 3 series B58 forum and doing upgrades first hand. If you dont plan on running ethanol, you wont see much benefit from the upgraded fuel pump.
The value in the B58TU pump is finding one used for a lower price. During the peak of the fuel pump era (beginning of covid) new ones were going for $1000 and used for around $800. Many people bought them because they couldnt wait for aftermarket options.
There will inevitably be a segment of the market that goes further down the rabbit hole and buys the next step up in fuel pumps and will be selling their B58TU pump to recoup costs.
I bought mine from pure800 as a used unit. They were used for testing their turbo upgrades and sold after.
Regarding the heat exchanger upgrade, not cheap...I believe Kevin Germain/Kern documented doing this himself on his 4 series.
What I would recommend you concern yourself with first is if your 240i has the rockguard installed or not, or you'll be considering the above mod (or radiator replacement) inevitably, without a choice in the matter, when you catch a stone into the radiator.
Mine is a 2017 but build date is prior to the rock guard revision, so I'm trying to figure this option out right now.
Originally, these were around $1000 when I first looked into them. Prices have fallen to $600 and it includes a rockguard.
https://studiorsr.com/products/csf-b...-charge-cooler