With struts/shocks, you get what you pay for. If you intend to keep the car, especially since it's a Boxster (good handling should be important to you, if you own a mid-engined Porsche!) spend more on this item, don't cheap out.
If you sell the car, keep used shocks, or if you are going "in there" for some other reason before you can flip the car, sure - cheap out! If your buyer doesn't pick up somehow looking at recipts, based on what you say, or on a pre-purchase inspection, knowing the cheap parts used, the test drive will initially seem ok.
As another cheap option, EPS sells inexpensive strut inserts which can be retrofitted into the OE strut bodies.
https://www.europeanpartssolution.com/shock-absorber/
I wouldn't expect the cheaper options to feel very "new like" after 20k or so miles. Get a quality shock, and you'll get 100k+ miles of good service out them.
Another viable option is buying used, low-mile OE shocks. If I were buying a used car, I'd actually give preference to used quality shocks, over a new, cheap aftermarket shock.
My 2 cents... (maybe based on some very bad experiences in other cars getting very short service life out of cheap Monroes, aftermarket Tokico's, etc).
OE Boxster shocks are really some of the better quality shocks out there! Bilsteins are some of the best in the business. The comment someone made they are "overpriced" is absolutely uninfomed.
Remember, again... with shocks, you get what you pay for.