Which MTL RTA to buy.

Greetings.
I currently own a kayfun prime sxk clone and a siren v2, i was wondering if any MTL experts here can recommend a better rta, the siren v2 is pretty good but i find the flavor a bit muted, as for the prime, its working well enough but wanted to try some other tanks before i commit to an original kayfun (if its worth it) any suggestions please ?

I love the simple and leak free SXK Doggystyle, got mine from Fastech. Pros -good flavor, easy to build on, don't leak, inexpensive. Cons- have to use the little blue screwdriver in the air slot to open, but thats easy. Like them better than my SXK kayfyun clones. Have about 10 now all Ive used for the last year or so lol