If you mean the Vu+ Ultimo 4k, its an Enigma2 device and it will do IPTV brilliantly but is more complicated to set up than the other boxes you have tried as its a satellite box that has to be hacked to do IPTV.

It will do kodi through an unofficial plugin, but not Terrarium as its not android.

/u/danny121pt makes a very good point. Buying the most expensive box you can find won't necessarily make it better than the others. By all means, go Enigma2 if you want a more customizable experience and like to play around with technology, but the Ultimo is overkill if just for IPTV!

Zero4k is the way to go if all you want is IPTV.

Plugins are like apps. However, this is NOT an android box so don't think you will be putting a bunch of apps on it. The plugins typically control a function on the box. There is a kodi plugin and other IPTV plugins, like Xtream-Editor, but its not remotely similar to what you are used to.

Spending £480 on a Vu+ Ultimo 4k is madness unless utilising its FBC tuners for Multi Sat purposes.

If IPTV only then Vu+ Zero 4k is worth it, can get dvb-s2 (single tuner i.e freesat) or dvb-c/t2 (cable or freeview aerial)

Its good for iptv UI the Zero4k, I have one, but E2 is only as good as the user setting it up and tweaking to sort themselves and learning the process, its not add a mac and click play like a Mag etc.

Can I ask what not satified with current devices? whats main reason for a new box? and what supplier?

can you please explain the reasons why you are not satisfied? then experts here can guide you better

If you're not satisfied with the boxes, what exactly aren't you satisfied with? If it's the pictured quality it, it's not the fucking box, it's your piece of shit provider or your internet, as each of those boxes are perfectly fine/high end and will deliver a great picture.