Nothing outwardly wrong with that system design, and is a standard air-separating surge tank with internal high-pressure pump and regulator, fed by either an in-tank or inline low-pressure pump (electric or mechanical). Surge tanks have been very common in EFI systems for over 40 years, and stock in millions of cars and trucks. They can be designed with fuel return from the fuel rails to the surge tank or returnless. We designed a couple very similar setups years ago, but dropped the commercial plan after the patent office said there were conflicts. There are in-fact many similar systems in OEM vehicles, so it wasn't worth fighting the legal battles.
We do however make them for our own use, and they do work very
well. The flow of a mechanical pump at nearly zero pressure is high, and there is no tiny needle and seat to restrict flow.
It's easy to pump directly into a container to measure free-flow (just like the service manual shows), so test yours if you're concerned. A pump is a pump, and just needs to meet flow requirements. Note that the low-pressure pump flow only needs to be the average
flow your engine requires over time, as the surge tank will make-up for high-power consumption shortage when necessary. That's one of the points, and allows stock or undersized fuel systems to properly feed much higher power on-demand.
Another purpose is to feed the HP pump with bubble-free fuel, even if the main tank pickup is sucking air (typically from sloshing low fuel), until the reservoir (surge tank) is empty. In carburetors, air separation is the function of the fuel bowls. This allows fuel to be used from an un-baffled or un-sumped main tank to nearly the last drop without lean-outs or stalling.
The size of that unit is rather large for most applications. I have not tested that unit (and have no need), but at 500hp, 1/2 gallon will feed at full power for about 45 seconds with no
fuel feed from the main tank. That makes it capable by math of over 800hp for ±30 seconds and with that pump's flow. That's big for street. We generally size ours for 15-20 seconds at full power for street and strip and most track applications, again noting the average consumption and max time without main tank fuel feed. Impact danger is no greater than other systems, with most EFI setups using impact/rollover electrical cutoff switches to stop fuel flow immediately, even if the engine is still running. Hope that helps.