Well, that's a pity (that Zoiper doesn't have heads up notifications for SMS messages) given that it most certainly does have heads-up notifications for SIP registration/deregistration. Seems like if you are going to have support for it for that case, it makes most sense to have heads-up notifications for SMS messages too.
Curious, why do you want to know phone brand and model? Is it relevant to Zoiper having heads-up notification for SMS messages?