I've actually had pretty good luck with PSI's low-end stuff. I stick mostly to the Funline series slimlines and Euros, and so far, so good. My one complaint about the slimlines is that the design of the clips can snag a shirt pocket if you're not careful. Not so with the regular series of slimlines. The Euros are great, and surpass my expectations, especially for the price. I don't mind the tenon a bit, and I feel that it gives a stronger bond with the center band. If I could make one change to them, it would be to taper the circumference of the ring part of the clip to match the taper on the finial. As it is now, it's cylindrical, which interrupts the shape of the upper barrel for that 1/16th of an inch or so. I'm still impressed with the result, although the lower end stuff is strictly gifted, and not sold.
I've had good luck with the transmissions, although they need a drop of oil to work smoothly. Higher end transmissions are better, but I don't think I would know the difference if I wasn't looking for it. As it stands, most people are used to junky clickers and throw-away Bics, so even the basic twist mechanisms seem like Cadillacs by comparison. A touch up on the ends of the barrels with Rick Herrel's sanding mill makes a big difference, too. Speaking strictly of the transmission, I'd put my Funlines up against a store bought Cross pen any day.