T-MOBILE UK/BB Pearl 8110 question

[Acidox]

Ok
So as much as I like BlackBerrys, this Pearl is god awful.
Fair enough, I came from a Bold to this (Long story, Orange were changing price plans and I needed a new phone quick yada yada)

Anyways, I have that Pay Once deal, so currently my BIS account has unlimited internet & email until like, next September. So I really don't want to lose out on this, but I DO NOT WANT THIS FRIGGIN' PHONE!

It freezes, all the time. Then it takes about a century to reboot.
Music player just randomly stops working sometimes
Phone is slow
And SureType, even though it's better than I expected, is still not as good as it's cracked up to be.

So finally, my question is:

If I went into my T-Mo store, or rang T-Mo UK, do you think they will let me change phones?

And what I mean by this is do you:

a. Think they'll refund the handset price and just let me buy a new BlackBerry and apply my BIS account to that?
b. Give me a different model BB and make me pay like 30/40quid?
c. Be lame as **** and say "Well, we can change the Pearl for another one"

Thanks.