Tannoy and Dynaudio are two completely different animals. Their respective "house sound" is just going to be different and it is not surprising that you prefer one over the other. Cost really doesn't have a lot to do with which you prefer.
You may have already covered this territory, but the only recommendation I'd have before you make a final decision is to make sure you've listened to an extremely wide range of music on both. You've probably already done that with the Dynaudio since you own them, but resist the temptation to make a decision based only on demo records or a narrow genre of music.
The point of owning a stereo is to enjoy music. If you can have more enjoyment for less money, go for it! Use the savings to buy some more music.
You may have already covered this territory, but the only recommendation I'd have before you make a final decision is to make sure you've listened to an extremely wide range of music on both. You've probably already done that with the Dynaudio since you own them, but resist the temptation to make a decision based only on demo records or a narrow genre of music.
The point of owning a stereo is to enjoy music. If you can have more enjoyment for less money, go for it! Use the savings to buy some more music.