Here is the thing. My wife were on an extended road trip of the Western United States and had the opportunity to stay at many different hotels, b and b's, and resorts. When we compared them all side to side for comfort and value added features and amenities, this hotel property in Santa Monica ended up at the bottom of our list (out of 7, including other BW Plus properties).
First let me focus on the positive. It did deliver a pretty standard, clean, secure room, circa 1990. Price was moderate, compared to other similar hotels in the West Los Angeles region. Yes, our stay was relaxing and uneventful. It was pretty far from the beach, but we knew that beforehand. It was located a few blocks from the LA Metro Rail system, which I think was it's best positive, as it allowed access to the rest of the city for $1.75 one-way. And, by far, it had the strongest free Wifi signal of any hotel that we stayed in (that actually extended as far as 3 blocks from the hotel!).
If you stay at the BW Plus Gateway in Santa Monica, it should be a decent stay.
However, when compared to other more modern hotels (including Best Western Plus) that we recently stayed at, we were disappointed to find that there was no free breakfast included, though there is an IHOP restaurant downstairs with LUNCH and DINNER discounts for hotel guests. And it may be a little thing, but after many days on the road, we were disappointed to learn that there was no guest laundry (coin-op), necessitating a late-night laundry expedition down Santa Monica Blvd. Parking was free, but the underground garage was decidedly old, very tight, and a bit creepy, as it was open access from the street. Being frugal/practical travelers, we had some of our own food with us. There was a mini refrigerator in the room (good), but it was unplugged, and required moving the whole cabinet out in order to plug it in (bad). Also, we had grown accustomed to a microwave oven at other Best Western properties, but no big deal (just a bit more missing value). Finally, not necessarily their fault, but our room was directly in front of the elevator and adjacent to the ice machine/vending machine and the sounds of Monday Night Football could clearly be heard from the adjacent room. This made our stay a bit noisier and less private feeling.
Overall, I would conditionally recommend it as an "ok" overnight option. It was not terrible, we thought. But, there are those small things, the "plus" in Best Western Plus that seemed to be missing (that were included at other BW Plus hotels). less