Citation from Piper?
Sorry, no can do, as Piper went out of business many years ago and New Piper never built the PA38.
However, AOPA in the US has high credibility and you may wish to read this article, which I would rather rely on than Wiki.
http://flighttraining.aopa.org/learn...icles/0107.cfm
A significant extract says "Flight instructors we spoke to feel strongly that the Tomahawk does what Piper intended. "It's the best primary trainer ever built," says Jim Tafta of Richmond Flight Center in West Kingston, Rhode Island. "The student is well trained, and
they can't get away with some of the things they can in other trainers." The feedback is overwhelmingly positive, with one caveat: This airplane, though a trainer, still demands proper training of its pilots from a qualified instructor. Those with the training have flown the Tomahawk for thousands of hours without incident."
NB: My italics and emboldening.
I believe I know enough about the C152 to comment on it's general effectivness as an ab initio trainer compared to the PA28, but not enough to comment on it's stall/spin risks versus the PA28 as I am not experienced enough on type in that respect.
Let me know what part of that you don't understand.
Also, kindly note that I have claused my comments 'ab initio' trainer throughout.