Actual cooking surface is 17x9. They include the handles to get 19.5x9.

This griddle is not bad at all as long as you care for it PROPERLY.
To begin with, the "preseasoning" that comes with it just plain sucks! I tried it right out of the box and food stuck to it 100%. I already knew it would just by looking at it but for the purpose of testing, I did it anyway.
In my opinion, the best thing you can do before you throw food on this griddle is to get rid of the crappy layer of seasoning by scrubbing the whole thing with a NON ABRASIVE sponge and grease cutting soap.
DO NOT THROW THIS IN THE DISHWASHER!! It's cast iron people, it will rust fairly quick if you leave it wet for even a short period of time.
After you wash it thoroughly, immediately pad it dry.
How I reseasoned it:
I threw it in the oven and turned the oven on to maximum heat and let the oven "bake" the griddle for an hour. After this, I just turned the oven off and let the griddle cool down enough to SAFELY take it out and place it on top of the stove. Grabbed a lint free rag and wiped any residue from the previous seasoning. After this step, the griddle was ready for re-seasoning.
I cook for a living so from experience, I believe the best thing you can use to season any griddle, pan, etc is a non stick cooking spray of your choice. Cover the entire griddle with the spray and wipe off any excess buildup. I placed it on my stove burners and turned them on to high to heat up the griddle. WARNING: This process will create smoke so make sure you can ventilate your working area properly.
Leave the griddle on high heat for 2-3 minutes and then turn off the heat and let your griddle cool off completely to room temp. Re-apply the cooking spray to the entire cooking area and heat it up again under medium heat. This time leave the griddle on the burners for 10 minutes or so, so it has more time to absorb the oils from the cooking spray. Again, this process will create smoke so ventilate properly. Turn off heat and let cool down to room temp. Re-apply cooking spray, wipe off excess and place it under low heat for an hour. Make sure you keep an eye on it every once in a while just in case it starts smoking. Turn off heat and let it cool down again.
After this, it should be ready to be cooked on and it should provide enough non stickiness for most foods. Keep in mind that some foods, no matter how good the non stick aspect of any pan, griddle, etc is, will still stick to the cooking surface. For these kind of foods just make sure to use a bit of the cooking spray before placing your food on the griddle and you shouldn't have any problems.
Repeat the re-seasoning process when you notice food is starting to stick to it again.

THE DON'TS WITH THIS GRIDDLE:
- Do not wash in the dishwasher!
- Do not use any soaps for manual washing! Just warm water is enough. (Soap breaks down grease and therefore will affect the coating of the griddle)
-After washing, do not let it stay wet!
Cast iron rust easily and quick so make sure you pad dry your griddle immediately after washing.
-Do not pour cool water on the griddle while it is still hot or you may crack it. That's just common sense, right?

I've had this griddle for a month now and it still looking like new and working great.
If you know how to take care of things properly, they will last you a long time.
One thing I noticed is that it has warped in the middle. Enough to notice but not enough to worry about it.
I have used the flat side the most so this is the side I season regularly. I have used the grooved side once and just like the other side the first time using, food residue stuck to it but came off fairly easy with a non abrasive brush and hot water.
I LOVED the taste of my steaks cooking them with this griddle.

OVERALL:
I think this griddle is a good value for the money spent and as long as you care for it properly, it should give you plenty of years of great use.

Looks perfect for its use

I bought this grill a year ago, and it has just gotten better every time I use it. I use the flat surface for pancakes and sandwiches, and the other side for grilling. Others have talked about the grill being warped, my was not.
My stove is kind of strange, one burner is hotter than the other, so I have to adjust the burners accordingly when making pancakes and sandwiches so they don't burn. I have a large wok lid that I use when making grilled cheese sandwiches, they turn out perfectly.
As far as the grill side, this grill makes perfect steak, chops, chicken, and shrimp. I have used it for shish-kebab and the only thing you have to do, just like an outdoor grill, is soak the sticks if you are using wood. I made grilled loin lamb chops by putting water soaked fresh rosemary sprigs on the grill and then grilling the lamb on top of that. The lamb took on the wonderful flavor of the rosemary. I also cooked skewered shrimp for shrimp salad.
I live in an apartment, and I have a pretty good fan over my stove. I make sure the kitchen window is open, and with just that I very rarely have much smoke. When my fan broke, I just opened more windows.
How do I clean it? I clean it with milk dish soap and water. I have a stiff plastic brush that I use on the grill side if a little meat has stuck to it. Then, I put the grill back on the stove, turn the burners on and leave it until all the water has evaporated. I have no issues with rust, and the grill is getting more and more non-stick the more I use it.

Have a Samsung gas stove. Grill that came with stove 1 sided only. This fits nicely & will have the 2 sides to work on. Also purchased Blackstone Griddle Seasoning & Cast Iron Conditioner which I will use prior to using the grill. Will update after use.