Recommended UK Training providers for CREST CPSA / CRT

I’ve learnt a huge amount so far from HTB boxes, but I would like to take the next step and study towards a formal qualification, most likely CREST CPSA and CRT. There seems to be so many companies out there offering online learning, but it’s hard to tell if they are any good, and while I have the money set aside, I’m not prepared to waste such a sum! I would appreciate if anyone has any experience with a CREST (or CHECK) training course (preferably online-based as I’m a couple of hours from London) and whether they would recommend it. Ideally I’d like one that offers a minimum of 4 months lab access as I’m going abroad in a month for about 6 weeks, and I’d like to get started before then. Budget is about £1k for each exam course, although I’ve seen both offered for <£900. Companies I’ve seen - Austerbury, ISCI, IhackLabs.

Many thanks in advance.