Yes, anything that is branded with "powered by SimplyCast" can have the logo removed, so long as that is included in your pricing package. The same restrictions apply: it costs 25% of the cost of the level in that channel.
So for example, if you bought a Professional-level Email package but bundled it with Fax and SMS, the 25% would only apply to the cost of the email, not of your overall package.
Removing a company logo is great for keeping confidence in your brand up, as you don't look like you're outsourcing. It's also really good if you're an important office or civil service to keep things professional and uniform.