Turbo,
I mostly use DupliColor. However, you have to be careful what you spray it over. If you spray it over an enamel color, you will have a disaster. If you spray it over Duplicolor laquer, the results are beautiful.
I have used Tamiya clear, but only over other Tamiya colors. I`m not sure how it turns out over other enamels/laquers. As is well known, with Tamiya clear you have to either spray it on immediately after the color, or wait for the color to fully cure (2-4 weeks at least!!!). That is the main reason I avoid Tamiya when I can.
This model was done with all Duplicolor laquers, including about 10-12 coats of clear:
