The salary is low compared to average graduates in first and second year(21k and 25k), however if you have been struggling to find a job then you wont be too fussy.
Relocation - you must be available to be placed anywhere in UK(including Scotland and NI). Also only a weeks paid accomodation when moving to a different city? It needs to be much longer than that.
The jobs available after training really depend on what clients/opportunites are available at that time, if you get a good placement you will love it, if not you won't, simple as that. Not everyone gets placed with the client/role they want.