I was also thinking about this
Bresser Bresser Safari 20 to 60 x 80 and tripod kit spotting scope due to it being cheaper/having better optics/nitrogen filled/having a tripod with it.
If I come into any money which is desperately unlikely I might have a look at the pro version of the first scope I mentioned (
Bresser Optics Bresser P90-pro 25 - 75x 90mm spotting scope), which looks good too.
I usually tend to think that bigger=better with zoom etc. but I don't really know if in birdwatching I'll ever need the extra 15x zoom over the 60x.