Given that this hood has an aperture area approaching 8 square feet, even with a short duct run one would want at least a 1000 cfm blower. The rated CFM is not what you actually get. Generally you will need a compatible source of make-up air. There are some exceptions. (See the many threads here on that topic.)

In-line vs. internal may not make much difference, noise wise, but that will depend on their relative designs. In-line raises the question of whether it will be accessible and whether it will be obtrusive if the duct is exposed. There are also external blowers that can be mounted on an exterior wall. These provide their own duct "cap". Broan/NuTone have some, I believe, among others. Compatibility with the hood's fan control is necessary, and this is an investigation on its own if the blower is not specifically compatible.

I would expect that Bluestar buys their blower assemblies from a blower manufacturer such as Broan. Wolf does.

kas

Thank you kas! I wonder how one finds out who makes their blower. I did a little searching today, found what sounded like a really good inline blower on sale. I was a little surprised to figure out that the blower itself was over 17" for a 10" duct. I may not have that much room...

Any chance you can go with a remote roof mount or exterior wall mount blower? I ordered my Prizer (Bluestar's parent co.) with a 1000 cfm remote. It works well with my 36" RNB with griddle. It looks exactly like a Thermador/Tradewind VR1000, so it's possible they use the same blower...

In-line blowers are typically axial fan type, and the fan motor is located centrally in the path and is fairly large. To get good flow the blade tips have to extend much farther. This may yield lower blade-tip turbulence noise than a similarly capable, but smaller overall internal blower.

Fantech has a page with fan curve data for all their axial blowers. See this link for more information:
Fantech pdf

kas