Also, a plug for Wingsung! They'll look very similar to twsbi or parker 51 at times, but imo they've added some little touches that improve on the twsbi.
Yes, definitely! I just bought a few Wingsung 3008s from eBay (a few dollars each, I think) and they're super-smooth. Couldn't believe I got a TWSBI-like piston filler for that cheap. Only downside to the cheap eBay pens is the shipping time...