Salt Nicotine in a Geekvape Aegis is not suggested.
The Geekvape Aegis Legend 2 kit is not designed to be used with Nic salt. The reason for this is that the tank on the top is sub-ohm. This means that it will be run at a higher wattage and produce very large clouds and a lot of vapor. This will be too much with nic salt. Since nic salt is typically found in the strengths of 10mg and 20mg, there will be too much nicotine delivered to your system too quickly.
The best type of liquid to use with this kit is freebase liquid which will be in lower strengths such as 0mg, 3mg, 6mg, and sometimes 12/18 mg. If you are using one of Geekvapes smaller pod systems, these are above ohm. This means that they are run at a much lower power setting and are meant to be used with much higher nicotine strengths. These devices will also produce less vapor and instead will be more focused on nicotine delivery.