Im torn between a 650 cfm vs 1200 cfm machine. Im looking at

On closed machines (router tables, jointers...) 650 is perfectly adequate.
On open machines (CMS, TS) there is a big difference.
I just went from 1hp to 2hp for that reason.

Once again though, I will recommend used equipment. I bought a used 2hp
canister unit that had never even been turned on for US$200. (well actually
I had to buy a 2hp and a 1hp for $350, and I sold the 1hp for $150). You
probably won't get this lucky, but it is still worth looking.

BTW, your 2hp King DC isn't anywhere near 2hp, nor will it do 1200cfm. 2hp
motors will be about 16a. Also, having only one felt bag will really choke
the flow off. Either go for a canister filter or two felt bags. Canisters
are much nicer, but also more expensive.
I also take offense at their claiming 52-62db for the 1hp; it is only near
52db when it is in the next room. I haven't seen the machines, but based on
their advertising, I would advise against King.