Product brochure states that 750g can route "up to 580Mbps throughput with larger packets, and up to 91500pps with small packets". The text doesn't go into specifics about what kind of traffic that would be, I'd assume they are absolute maximum numbers posible. If you compare it to test results of RB750Gr3
, these numbers are 5 times to 10 times lower. And to put the numbers in perspective: many users of this forum find the number under "Routing - 25 ip filter rules - 512 byte" to represent typical real-life performance pretty well. Which means that even the modern ancestor of your device would not necesarily be able to handle your forseen 635Mbps. But the same rule of thumb and approximated performance scale would indicate max throughput for your current router at around 40-80 Mbps which is much less than your bandwidth of 210Mbps meaning your current config is not very complex.
So you might want to try with hEX
(the price tag is not excessive). Or select some beefier device, such as hAP ac²
(you get dual-band wireless as bonus) or RB4011
(has 10 RJ45 ports and SFP+ cage ... there's model with wireless as well).
As to configuration migration: I advise you to start afresh. It is quite likeky your current RB750g is running obsolete version of ROS and some thingsa have changed substantially in last few years. Default firewall rules have evolved significantly and current ones quite decently secure router itself and LAN behind it. It would be pitty to ditch the modern defaults just to nake task of migrating configuration easier.