Location, location, location - it's perfect! The room was small but just fine. Has all you might need: wifi, hairdryer, ironing board and iron, fast-boil hot water pot, coffee/tea. The bathroom was large and updated; good water pressure. Staff were great. Breakfast was fabulous (both hot & cold), though not standardly included unless bundled with your room at a higher rate or the €18/pp/day paid separately (the operator is actually a separate Asian Fusion restaurant, but the breakfast menu is European/American and plentiful.
Only real downsides: As others mention, the great location can also get very noisy at night, especially on weekends. I didn't mind, but you might. And the hallways and common areas could use a re-painting and new carpeting.
Did not use the spa facilities or services, so cannot comment on that. Calling this a "boutique hotel" might be stretching it a bit. But it is a solid 2-3 star traveler hotel with some upsides like location and the breakfast offering on site.