I think you’re referring to a Fritz 7530, which is good enough for what most people will need it to do. And I’m not going into other ISPs offerings because it’s unfair on Cuckoo, but lets just say, there is no point pairing a FritzRepeater 3000 with a 7530 because the repeater has higher wifi speed capability than the router!
Personally, I use a 7590 because it has the ability to use an analogue phone line for making calls. The router (and the 7530) has a DECT base built in, so I can control all my calls, contact lists etc from the router. It makes life simple. And yes I’m old fashioned in the sense I still prefer to use a landline to make calls at home than a mobile.
The 7581/2/3 are the bonding modems. Very pricey at about £300, but the 7583 has G.Fast bonding built in as well as backwards compatibility. But where these routers are fantastic in Europe is because a lot of CP’s support the subject of this post. Not in the UK, seems to be a lot less flexibility - although G.Fast is really a non starter now, and its development and deployment was a complete waste of money.
If you want the best mesh system, get yourself a Fritz 7530 and pair it with a FritzRepeater 2400 (although you will need a europlug converter) or you can get the Fritz Repeater 3000 with a UK plug for another £30 usually on known big selling website.
My main reason why I like Fritz products is because I can see things like the picture
and get really nerdy with settings and statistics.