The STK on my Nexus is shown after I activate and de-activate the airplane mode. After that I can see the STK menu with one option: "toggle". When I click on toggle it seems to load the next menu for a nano-second, but then I'm prompted to the same menu with the same option "toggle"... :(

Just so you folk with no STK on your expensive phones know: It does not show up on my cheap phone either. A BLU tri-SIM I got for $27.

Wonderful. I can't receive SMSs sent from my NL toggle to my main italian number. I think I'll get an UK toggle... (at least they have micro-sims - my main phone is an Xperia Z)

I don't think they have. When I ordered a nano-SIM, they sent me a 2FF mini-SIM which they had cut by hand.

Ouch. The SMS routing problem remains. I can't send SMS to numbers with H3G native prefixes (+39 392 - +39 392). I think also that they don't send SMS to numbers with native MVNO prefixes (+39 37x), and I'll test that. As a first step I'm going to write them an email asking to fix this problem (but I don't think they will do). As a second step I'm going to look for a sim cutter (maybe in the same email I'll ask them for a micro-SIM)... :D

Thank you for your warning.

EDIT: yes, it's confirmed. No SMS on prefixes of H3G and every MVNO.

EDIT 1: On my Bip Mobile sim (+39 373) an SMS arrived now, with a delay of more than an hour. So SMS service seems totally unreliable. On my main number still nothing.

Bear in mind that the menu can show up in strange places. On my Sony Ericsson Z750a (non-smartphone), it shows up under the entertainment menu.

Yes it can. I just checked ALL the obscure menus to double check.
No luck. One would think this kind of thing would get solved over the years.
But no.

Thanks for that. On my old Sony Ericsson K600i (from 2006), it likewise shows up under the entertainment menu (with the icon of a games console controller).

Phone always indicates roaming
 

I have a fairly basic Samsung GT-E1190 mobile which, even when in the UK, permanently displays the roaming symbol on the screen.

Even if I enter the Toggle menu and select "Manual > UK" it still displays the roaming symbol.

I called ToggleMobile and they said to just leave it in Automatic and it would work correctly.

My question is how do I know whether it has selected the local UK number or if it is actually roaming and going to create excessive call charges?