It might depend if they are truly penalty clauses or whether they are liquidated damages (sometimes the terms are used interchangeably despite the difference).
While there has been a tightening up of the enforceability of penalty clauses, there is still a strong presumption that if both parties are properly advised and of a similar standing, they are best placed to agree on what a reasonable penalty amounts to. It can be challenged if the penalty amount is out of all proportion to the losses incurred, but these losses can include some less obvious aspects such as reputational damage.