The RGW you have now is only a single band which is just a 2.4Ghz. Now since you are using ADSL you may not see a big difference if you move to Ultrahub. But in saying that Ultrahub is Dual band which means you have a 5Ghz as well.
the 2.4Ghz band is used by a lot of devices nowadays so that is actually very overused and congested.
If you upgrade you may see a difference on the stability and the latency but it all depends.
The RGW you have now is End of Life so its always better to go to the new RGW. you may even see a Speed bump ( very miniscule) and if you get fiber you will see a big difference.
Device and CPE Engineer - Fixed Access Vodafone.
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