Before we can recommend any nicotine we need to know at what level of nicotine you you plan to vape at and the kind of equipment you will be vaping on.
If you are a new vaper ( just quit smoking) Salts may be the best choice because you can mix at higher amount’s.
Freebase nicotine is recommended at 18mg/ml or less in a mix without being harsh in a mix.
MTL or DTL really shouldn’t matter. No difference in mixing. What does matter is the delivery method. For example a low wattage pod (9 watts or less) you will need a higher nicotine content than a 100 watt RTA/RDA or a AIO.
For your purpose tho a fresh freebase should be fine.
Thats makes sense, just a last question, what is the difference between freebase and what I would consider a “normal nicotine” eg:
Scrawny Gecko Nicotine VG 36mg
Call me crazy but freebase would be normal nicotine to me. Salts are normal nicotine with the addition of an acid to change the PH. Since I don’t know the lab your ordering from to read the description of Scrawney Gecko I have no idea. I do know different acids affect the smoothness of the salts. My guess would be they are marketing a smoother or more harsh salt for throat hit.