Pager's versus SMS

I have tried an SMS service for Bird reports for a few years and still come up with the same problem (reports in the evening or bird's seen yesterday), This can be irritating if you have to travel to see a specific species and it's gone.
I am thinking of trying a pager service, but which one?
Anyone for or against this idea, let me know.

(Assuming you're in the UK...)
Personally I find texts from BirdGuides pretty good on the whole, although not perfect. Part of the problem I have (and perhaps you do, based on your comment) is to do with phone reception - sometimes the messages just don't get through, and I don't know if pagers do any better on this score. Part of it is that although with Birdguides you can customise what you want to receive texts on, and this works pretty well, you still end up with some stuff you don't want. For example, I end up with tons of messages about Cranes in the broads, because Crane is rated as a scarce species across the UK as a whole, whereas it's a resident here in Norfolk and certainly not something I want telling about every so often! However, overall I'd give them a 9/10.

Never had a pager - anyone else got advice on this for Trevor?

Thanks
Yes, sometimes I get texts which can be off putting(Bird seen yesterday or flying over).
Please be reasured I am not knocking the Birdguides service it is very good, I just wanted to know the pro's and cons, before comitting myself.