Yo Fish - Talk about serendipity - I got a notification on my IPhone of your post literally while I was tossing the cast net for BG off the dock.
So, yes, I'm still using it, and yes I still like it - but it can be a tad trying at times. Here's some general feedback and tips:
1. Throwing a cast net is far easier when elevated from a boat or a dock. Further, it helps being North of 5'8" if you're using a 5' or larger cast net so the net doesn't drag which really impedes casting motion and deployment.
2. I learned the frustrating way via trial and error with a 5' net over several days. 5' isn't huge, but they make them smaller [3.5'; 4'; 4.5'; etc.]. I recommend starting with something 5' or smaller per Dave's suggestion.
3. Review online tutorials as they can teach you some great tips and help ease the learning curve. It never occurred to me to look online for tips until my bad habits were already fully ingrained - but encourage anyone learning to go there first.
4. I personally prefer nylon vs. mono nets. I think they are easier on fish and tangle less frequently. Also, think Douglas Net Company - I love their products thus far and they are far more affordable than other inferior brands I've tried.
5. The harder I throw, especially into the wind, the less my net deploys. I learned it's far more important to perfect the timing/motion of the throw than to muscle it. Casting into the wind can be a frustrating/fruitless enterprise at least for someone at my skill level.
6. I learned to never cast where larger fish may be cruising [deeper water under pellets]. I have accidentally caught a few large HSB and SMB and I had to cut them out of the nets so I didn't lose them. Extricating them would have taken too long - likely ended as morts or at least uber stressed. Cast net repair is rather tedious work - so I focus my casts in areas where my target size/species will likely be. I only use cast nets for FHM, GSH, and panfish [BG, RES].
7. Removing BH from cast nets is a slow and sometimes painful process. I now simply stomp them in the net then shake them out in the grass. They are far more docile that way.
8. Get your target species feeding on pellets prior to casting - you can increase your success exponentially than throwing into dead water and hoping.
9. Fish get wise to cast nets rather quickly - I agree they must see the net coming. Smaller fish are less experienced/wary so temper your expectations in smaller BOWs - especially if you're casting from the same position like on a dock. Don't expect 10" BG and RES in every cast. Following 10 casts I typically don't catch much else from the dock unless I wait 30+ minutes for things to mellow. Casting at dusk or night increases the take significantly per other's experiences in the thread.
10. Don't be afraid to cast into vegetation - many fish hold in shallow vegetation and depending on the species the cast net won't pick up much green on the retrieve. American Pondweed is a great example - holds lot's of fish and I often don't come back with a leaf.
11. I also enjoy using an umbrella net for collecting BG around the dock. I've used several brands and they rarely hold up [Frabil, et al] until I found Douglas Net Company. So far I'm super pleased with it's construction and integrity. I typically will catch 50-75 YOY BG per net every 2-3 minutes even without bait. Helps me feed my YOY SMB in the reproduction pond for free. I hear they're good for Crayfish, too.
http://www.douglasnets.com/product.php?productid=6&cat=0&page=1