The perk of Danny's is the convenience. A car wash and oil and lube for $42 is great not to mention the time saved. However, they will try to upsell you to other services at EVERY turn so beware. The last time I had this many people trying to sell me stuff I didn't need was when I was in Egypt!
$42 can easily turn into over $200. I got a car wash and oil change last week and I was first told that I had a crack in my windshield (which they could easliy replace-they later acknowledged that it was bird poop and not a crack); they also tried to upsell me on premium oil and after that air freshener (and possibly upgrade tire treatment but don't quote me on that).
After they toook my vehicle to be washed, I got the call to the counter for the consultation where it was suggested that I would need to top off fluids and possibly flush my fuel injector (which I had had done a few months prior at my regular mechanic). I also notice on my receipt that there was a note that my air filter needed to be changed. This suggestion was made the last time I went to Danny's a year ago (which I subsequently had done with my regular mechanic).
So beware that they WILL try to upsell you and they are a bit aggressive and persistent but not unfriendly. They will ask you open ended questions about your vehicle servicing as a means to suggest services they can sell you.
Don't get me wrong, Danny's is VERY convenient is good value if you stick to your guns and I will definitely use them again.