I was very happy with the 536 I got when they first came out, to the point of moving up my plans for buying another for my vehicle.
The only big issue was with headphone usage. Some bad components found their way in the assembly line. Uniden has addressed this problem. They've also run into some snags with the Siren App, which will hopefully be resolved in the next 2 or 3 weeks. (The Siren App allows for "remote control/listening" - but the scanner functions just fine without it.) I'm unaware of any other major issues going on and I'm watching this site a couple of times a day.
This model scanner is about like anything manufactured. You'll find there are those who really like a product and those who don't have anything good to say.
I doubt that Uniden will be coming out with another "high end/does just about everything" scanner product this year based on history. From what I've seen in the past, it's about 2-3 years between new scanner products. The link below goes to the RR Wiki shich shows a list of Uniden scanners and when they hit the market.
There will be a learning curve, but if you've dealt with the 996T successfully, you have a pretty good base. It's probably like flying airplanes - going from a single engine plane to multi-engine planes - same principles, but a whole lot more details.
Don't be shy about asking questions - a whole lot of us were in your shoes at one point and many folks here don't mind offering up help.
I have had a lot of scanners over the years, even going back to the crystal controlled Bearcat scanners and more recently Radio Shack and Uniden scanners including the digital scanners. I finally got my BCD536HP several weeks ago and all I can say is it's unbelievable. I can use it like my Home Patrol scanner or program it like my BCD396. It gives you a lot of programming capability or can be very simple, what ever you like. The sensitivity is as good as or better than the 396 or HP-1.
I am now looking forward to the Siren App being completed so I can start utilizing the Wifi capabilities
Also the GPS function works great as well.
Have been using the Discovery mode on trunked systems looking for new ID's on the system which is also a good function. Haven't run into anything I have disliked yet. Great Scanner.