I am a non-native learner of English. This is the "yod-dropping" issue, when it comes to pronouncing words with letter ''T'', is it ok to pronounce some words British style and others American? Like:
I wanted(''wah-ned'', American) a better(''be-tza'', British) solution.
It is a little bit mixed up now because some videos I watch are made by Americans, whereas others are by Britons. As a learner, its confusing.
As mentioned, there are no pronunciation police to haul you off if you mix your styles - but as a non-native speaker you will already have a 'trade-mark' accent that people will judge your ability on [whether they mean to or not].
Because of that, I would pick a style & stick to it.
It's quite likely, depending on the strength of your trade-mark, that native speakers wouldn't notice the differences if you switched from one to the other anyway.
I think taking that trade-mark & adding further idiosyncrasy would be counter-productive, so...
US slang "I wahn-ned a bedder solution" - avoid.
British slang "I wan`ed a be`er solution" - also avoid, unless you feel truly confident in your glottal stops.
US or British articulate pronunciation "I wanted a better solution" - stick to that. Put the t's where they belong.
Having said that, we don't know what your native accent/language is.
In hugely broad terms - if you're Northern European people will probably think you speak with an Americanised accent anyway. Southern European or really anywhere further afield, people will have far less certainty. If you're Asian or South East Asian, most un-travelled people won't be able to tell which you are aiming for most of the time.
People who have themselves travelled a lot will always have an easier time of it when communicating with another traveller, wherever they're from. It's just the way of the world.
This may sound strange, but I think you can pronounce them however you like, as long as you realize that your audience will be trying to figure out where you come from. Be consistent and be yourself. Around New York City, the word "better" sounds like "bedder" or even "bedd-uh" depending on who's saying it. On the street it may not matter much, but if you are making a public address, it is better to pronounce the T's so that you will be clearly understood by all.
