If you search DLRE on this board, you'll get a lot of information, but in the end, it's spotty service. They've been "bought" 2 or 3 times over the past 5 years.
The one of the last times I took them from LAX (before those 2 or 3 buy-outs), I ended up waiting on the little LAX transportation island for 2 hours or so, for an "every-30-minutes" bus. Dispatch had no idea where any of their buses were. One the last time, they told me they increased their prices, and they were like $5 more per person. When I pointed out what their website said, they argued that it was an internet-only price. I pointed out on their site where the internet only price was (showing $3 off for booking online instead of paying on the bus). The guy finally gave me what the website said. The bus was PACKED, so if he quoted $5 more per person, that was an easy $100 for him. But I talked loud enough that the rest of the bus got the correct price.
But plenty of people have had a perfectly good experience, even recently. But, plenty of people have had the same experience as I did, even recently.