I too let shops do the big stuff, they have the air and the machine to do it well.......
Every Harbor Freight unit I've ever bought needed some type of work. Yes, I am a bit fussy, but I need my stuff to work. Crappy plumbing, poor legs/structure and getting parts such as wear items can be a hassle.
Pressure blasters make a complete disaster. They must be used out doors. Unless you can recover the sand (and if you do, one tiny piece will clog your machine SOMEWHERE,
) I've had stems from a leaf or things just as small create a complete shutdown and 30 minutes of clean up and remove time, then you have to wait to build up 120-150PSI again.
They blast like crazy for about 45 seconds with a full 33 gallon tank and a single stage compressor.....Then the sand barely pisses out and it's 5 minutes until you can blast again.
I own a pressure unit and a cabinet and I've had to modify them both and the pressure blaster rarely gets used now; I would rather recover the sand in my cabinet.
I am near 100% satisfied with the HF cabinet unit once I fixed it up
Size is your only limitation and everything BUT a frame fits. I use fine grade sand on everything (including aluminum) and it works well, but as mentioned, you do have to be careful with some stuff. Rubber will be destroyed and I'd never put a carb in there...... If I can't remove anything threaded, I do not blast that and I cover it with tape. Preserve whatever coating left that you can!! I see guys blast hubs all the time, then they're left with 4 rusty studs in a PC'd hub........................
All our government does is distract us while they steal from us, misspend our tax $ and ruin our country