You get what you pay for, but it's not all that bad. Free airport shuttle, free wireless internet access (though inaccessible from some rooms -- must call first to make sure you have a room with access). It's a bit old and run-down in some spots, and I had to change rooms because of some malfunctioning plumbing. But it's quite inexpensive, and the rooms were reasonably clean, with functional beds and free HBO.
There's even a free neighborhood shuttle about a 5-minute walk away, called the "Tempe FLASH". You cross Apache Blvd -- not for the faint of heart, as it's a busy multi-lane divided highway-type road -- and then walk up Dorsey Lane; there's a stop on the corner there with Lemon St. The shuttle can get you to a bunch of stops in downtown Tempe and ASU. There's also a regular non-free city bus across the street on Apache Blvd.
Otherwise, it's a 15 minute walk from ASU (the DaysInn.com website says 5 minutes, an underestimate).
The complimentary continental breakfast wasn't bad; a bunch of mini-muffins and danishes, coffee, and juices. The staff was nice, and helped out when there was a problem with the plumbing.
Didn't try the pool or the hot spa, but they looked decent enough.
No, it's not the Mission Palms (where I was attending a meeting -- hence, how I discovered the Tempe FLASH shuttle) -- in fact, it's about as far from that type of hotel you can get. But it's also a heck of a lot cheaper during peak season.
It is what it is, I guess. Mostly, a cheap, somewhat dated motel. As you'll see with other Days Inn reviews on this site, many of them are somewhat run-down, and this is no exception. There's a so-so Mexican fast food shop next door, at not much else (you'll have to walk a bit further or drive to get to the supermarket or other restaurants). It felt safe enough, I suppose -- largely because there just weren't many people around at the time I visited.
If you're looking to save money, I suppose you could do worse. But if you can afford just a bit more, I'd try for a nicer place, or at least one in a more lively neighborhood (e.g. near Mill St. or downtown?). It's basically a place where you can't pinpoint what exactly is wrong with it... but everything put together makes you want to stay somewhere nicer instead.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.