Sam, I have seen enough Shidduchim broken up over the Chassan asking for a too-expensive Shas (and the Kallah expecting a too-expensive ring).
Nebach. Two differences, though. The most expensive chosson shas is probably less expensive than the least expensive engagement ring, and the difference between a cheap chosson shas and an expensive one is relatively small, while an engagement ring can range from around $2,000 until, well, ein l’davar sof.