I would not go for a savage as they can be a real pig to work I have had two of them in the past and sold them both, not because things went wrong all the time but if something did go on it it was a real pain to work on. I have always thought that the tnx looked a bit cheap and thats what has put me of them but the ones I have actually seen go are really good and the layout is soooo simple on them. I don't know how much the Thunder Tiger MTA4 .28 is over there but in the UK the rrp is £60 cheaper than the Savage .25 and they are great trucks. Bigger than a savage, great for bashing and easy to work on and with a .28 in it they are quick too. I have one and I have been really pleased with it.
If you want something quick and agile then go for the TNX if you want a big brusier go for a MTA4.