The HFDC is fine for most, average hobbyist/weekend DIY needs. Yes, it is somewhat of a "dust distributor", but it does get dust and chips out of your planer/saw/jointer. It's better than a shop vac by far. No, it's not an Oneida, but it's not 1000$ either. It all depends on your goals: do you need to evacuate dust and chips from table saw from one saturday per month of making bird houses? At the price point, the HF meets your needs perfectly. Standing behind a drum sander for 8 hours per day in a production shop and need to pay for workers comp for employees? Get the Oneida.
I am perfectly happy with my HF, it has lasted 4 more years than the 1 year I expected it to last. No, it does not "collect" fines, and if you get a 150 DC thinking it will do so…..I just wheel it near a garage door, open it, and point a fan at it. That is, when I just don't disconnect the bag and vent it all outside.
As for the impellor "hack", I'm hearing bits and pieces of recent success on getting the Rikon Impeller, but "word on the street" is that Rikon does not want people doing this for "liability" reasons, and you have to prove Rikon ownership to get the impeller now (I'm hearing this 5th hand BTW). ALso hearing that WEN dust collector. P/N is 3403-022 Turbo Fan is same as Rikon, but 90$ cheaper. Not sure I'd put a 40$ impeller on something that spins that fast, but like I said, at the price point, worth a try. The Wen impeller is equally hard to find.
I believe the HF pulls 12.7 amps on startup. With the Rikon fan, it pulls 18-ish. Putting the Rikon on it will stress (and decrease life) of an already marginal motor. Again, at the price point, worth it IMHO.