t-mobile any good? anyone use 18185 over ride service?

[#1]

As title really. I have had good service for around around 7 years with t-mobile. They currently have a very good offer for me, broadband and homephone at unbeatable price. Currently f9/plusnet cannot get near it! Correspondence with plusnet gives me the impression they are not interested in offering me a deal like they offer new users! eg, the unlimited broadband with home phone, they want to charge me additional £1.50 per month just for weekend calls, whereas is included on website advert. A great way to retain loyal customers - myself 10 years standing with f9. I am seriously considering t-mobile, as I am fed up with f9 attitude to existing loyal customers. AND with the latest 1st October today (made me post this really) announcement, they will charge me 25% more just to retain 10gb broadband only contract. GREAT! This is obviously to force customers to include home phone, but in my opinion, will force me to look elsewhere.
F9 have for a number of years been a very reliable service, and still are. But I think my days with them are numbered.....
Any opinions t-mobile appreciated.
BTW, I did ask CS about 18185 use on landline and got the reply "Looking in to this for you, this isn't something we fully support". Surely it is either supported fully or not at all!
regards, FH

[#2]

Can't advise at all about t-mobile but 18185 definitely can be used (currently) on Plusnet Home Phone with no problems.

[#3]

Thanks for that. If I should choose to stay with f9, I only hope they don't remove it or charge a fee in the future.
On another note, I do feel that once a contract is established, eg my homephone, with 18185 operating freely, then for the provider to introduce a variation should be subject to a new contract, with the option for me to cancel at NO CHARGE. But, after all, it is phone/broadband companys we are dealing with!
fh