Congrats on the team-diversification and growth.

Several remarks

Speed 900's are getting very rare, and a lot of roboteers are looking for them , as their machines use those.
I'm talking/working on a 1 on 1 replacement, but it's looking to get expensive. Forget the current speedo's, that's for sure.

What brings me to Sabertooths. Maybe that a 60 amp one can digest a Speed 900, but the rest won't love the combination.
A Sabertooth 25A combined with drill/GR02 drives looks the best bet for now.
Team RCC didn't use them, so, no experience there. And with speed 900's, up to 4S a robotpower Scorpion XXL can do the job, but over that, it will struggle.
The TZ85's are the new standard, and those happely provide power to any motor up to 6S 80 amps (more than a standard series 3 heavy)

P&P from Belgium to anywere is hidious... But here an example of what we do with Hardox 450 3.2mm thin.