I have a couple of comments about dust collectors.
I had a Jet Vortex Dust collector that was 1.5 HP. Even though Jet rates them at 1200 cfm, that is complete nonsense. If you get 600 cfm, you will be doing very good and through a 10 foot flex hose less. The Dust Right at 3/4 HP says it will do 650 cfm...wrong. I have a much larger system and have tested mine with proper instruments and only get about 700 cfm through a 4" flex hose to my table saw....I have a 5 hp cyclone unit and I have measured up to 1850 cfm. (The reason that I have such a large dust collector is that I have other large equipment in my shop and have piped the shop with 6" PVC Duct.). I also have done a lot of testing on my own system to quantify the system.
The vast majority of low end dust collectors are tested in strange conditions and the cfm specs way over rated. It is unfortunate that companies over rate their machines. What they typically do is take off any filter or bag filter and test right at the inlet of the machine. If you do this with some dust collectors, you will burn out the motor. Wood Magazine in March 2008 did some testing and provided good test data.
In addition, the Dust Right has a 30 micron bag on it and will not do much to protect you. Remember that we want to collect as much of the fine dust down to under 10 microns.
I think the idea of a 6.5 hp shop vac with a HEPA filter and dust deputy is a good idea and works well for many people. The shop vacs only pull maybe 125 cfm but they have a vacuum level up to 10 times a dust collector. They will be very good for a scroll saw and smaller power tools.
I am a strong believer in good dust collection and the best you can get. I use a shop vac system on my scroll saw and it does a very good job.