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.
Uniden Scanners - The RadioReference Wiki