issue with ac87 is the internal architecture, not the stability. Internal architecture is bottlenecked so in a high performance environment you will run into issues. No issue if you only browse the web and watch videos and game a little bit but if used on a 1Gb/s connection and/or using with lots of LAN traffic is where the problem really starts.
Your choices are the AC68U, AC87U, AC3200, AC3100, AC88U.
AC68U - tripple channel AC wifi, less hardware acceleration but does the job well.
AC87U - hardware acceleration for wifi, has internal bottlenecks but has MU-MIMO (not sure how well this works)
AC3200 - when you need to accommodate to lots of 5Ghz traffic in a small area, also has wifi hardware accelerated
AC3100 - broadcom's MU-MIMO, also has wifi hardware accelerated but with a better internal architecture than the AC87U. supports LACP
AC88U - the AC3100 with a realtek switch for an extra 4 ports but connects to router at 1Gb/s so 4 gigabit ports only share 1Gb/s to the router CPU. Supports LACP
AC5300 - same use case as the AC3200 but with MU-MIMO, faster CPU and more hardware acceleration. Supports LACP
Thats a quick summary of the asus routers. pick based on your budget and use case.
RMerlin assures me that the stock 4 ports on all the broadcom based asus routers arent limited by a 1Gb/s to the CPU. ASUS uses the switch part of the broadcom CPU but different brands vary on their design and selection of chips so while im not sure if the 4 ethernet ports on all those routers only have 1Gb/s to CPU
@RMerlin says that each port doesnt share the same 1Gb/s link to CPU from switch chip part of CPU.
