SHS is mostly studio rooms - no full kitchens and most are not actual suites. I made the mistake of booking one of these when we actually needed a suite. The hotel actually had zero true suites in the building. Other than the misleading name, the chain itself is fine - it's usually cheap ($70-90/nt.).

TPS is mostly long-stay units, some with a few studio units mixed in. Full kitchens, 1- or 2-bedrooms. Limited maid service and few onsite amenities. I've stayed in a couple of them - usually at $90-120/nt. They are good if you are on the road for a couple of weeks but don't want to spend the $150-180 that a typical Residence Inn runs.

My only complaints with Marriotts branding are (1) SHS feature no real Suites and (2) I've recently learned that Marriott uses the term "resort" as a euphemism for "we don't honor the elite benefits". The brands themselves don't overlap much like Hilton's sometimes do. Hard to find a Courtyard that is a cut above the Marriott down the street.