I will add some help for the Taifun, which is to get the YFTK version and Do not get the Steamtribe version. I don't have the Steamtribe, but I do have a black YFTK. If you want an accurate reproduction of the real thing, so you can "feel" high end, get the YFTK. If you just kinda like the looks, but don't care about accurate measurements and interchangeable parts, Steamtribe is USUALLY okay, never mind-blowing, but a solid "look-alike". Many people want to try "legendary" atties, but if you want the real experience, you need a 1 to 1 clone, which Steamtribe rarely does.

EDIT: On the GTR, it appears you have missed a great option that is one to one, but lower cost than YFTK, while being much better than Steamtribe. They are in the 15-16.00 range, so within your range under a twenty. They are unbranded, but without checking now (im at work), i'll guess they are Wejoy clones, and should be great...check for reviews.
i searched "gtr rta" and all the tanks and accessories fit on a page. nice selection. SKU 9704120