If one is in a vehicle travelling (bus/train/plane) Should you pray right away when the time for prayer has been established, or wait til after you get off before praying. This is in the case one is certain there is enough time to pray the prayer after getting of the vehicle, (prayer will not become qaza.) There are usually many obstacles praying when in a confined space, such as having to pray whilst seated, very tight places to make wudu, and not beeing able to concentrate properly etc. But I know that the best reward and effect of ones prayer is at the very begining of the prayer, so I want to know the better option, even if both waiting and praying right away is permissble.

If you know that after reaching there will be enough time to pray properly then you should wait and pray somewhere that you can fulfil all the conditions of salah (eg standing)